The short version: No, the two Japanese ambassadors were not meeting with President Roosevelt during the attack on Pearl Harbor. This is, presumably, a mistake. Kichisaburo Nomura and Saburo Kurusu did meet with Secretary of State Cordell Hull that afternoon to deliver the 14-part message, but they did not meet with the President on December 7. There is no evidence to support the idea that the Japanese ambassadors had specific foreknowledge of an attack on Pearl Harbor; they seem to have learned of it that afternoon.

If anyone would rather have text of her address than a video/audio file, here it is.

The longer version: We should probably clarify some of the confusion surrounding the timing of this radio address and the attack on Pearl Harbor. This radio message was not delivered on the morning of December 7 or the morning of December 8, before Franklin Roosevelt addressed Congress shortly after noon. Eleanor Roosevelt here is speaking on the evening of December 7 on the US east coast. The attack began at about 8:00 a.m. in Hawaii, which was about 1:30 p.m. in Washington that afternoon. The exact timing of this radio address is elusive to me; Eleanor Roosevelt says that "The cabinet is convening and the leaders in Congress are meeting with the president." This would have been relatively late in the day; FDR first met with a "war cabinet" of government and military officials involved directly in war plans, then held a full cabinet meeting at about 8:00 p.m. (apparently not everyone arrived until closer to 9:00), then brought in leadership from both parties in the House and Senate at about 10:00 to provide them with information on what happened and request a joint session of Congress on the 8th. However, this indicates that her address went out at about 6:45 p.m. In fact, large-scale Japanese attacks on the Philippines would not have begun by 6:45 p.m.; that's usually recorded as happening around 12:40 p.m. on December 8 in Manila, which would have been closer to 10:40 p.m. in Washington; the air raids there were delayed by fog. Some attacks had begun on a US Navy ship anchored near Davao a few hours before that, but I don't know if that's what she is referring to or not.

In any event, you can forgive some confusion on a day like this. There was a fair bit of unconfirmed information going around and it took time to sort out what had actually happened and what was being erroneously reported.

Franklin Roosevelt was not meeting with the Japanese ambassadors on the afternoon of December 7 in Washington. He heard about the attack around 1:40 p.m., while he was in the Oval Study (not the Oval Office) with his aide Harry Hopkins. Frank Knox, the Secretary of the Navy, called to report the news he had just heard from Hawaii. You can see FDR's schedule for the day here; apparently he had a brief meeting with the Chinese ambassador at 12:30 before he took lunch. By some accounts, he was fiddling with his stamp collection when he got the news about Pearl Harbor.

The Japanese ambassadors had been instructed to deliver the "14-part message" to Secretary of State Cordell Hull at 1:00 p.m. on December 7. You can read more about that from u/Lubyak and me here. The message wasn't delivered until after the attack had begun. President Roosevelt called Cordell Hull to inform him of the attack almost immediately. Hull told Roosevelt that he had the Japanese ambassadors waiting to speak to him in the next room; Roosevelt instructed him to receive them anyway and not mention the attack, just in case the first messages they had received were in error. Hull met with the Japanese ambassadors, then read their message (which he had already read courtesy of American codebreaking efforts). He reportedly said:

I must say that in all my conversations with you [the Japanese Ambassador] during the last nine months I have never uttered one word of untruth. This is borne out absolutely by the record. In all my 50 years of public service I have never seen a document that was more crowded with infamous falsehoods and distortions - infamous falsehoods and distortions on a scale so huge that I never imagined until today that any Government on this planet was capable of uttering them.

He did not shake their hands as they left. He did not inform them of the attack on Pearl Harbor. The Japanese ambassadors reportedly learned of the attack when they arrived back at their embassy after this meeting.

You can't prove a negative, but there is no evidence to support the claim that the Japanese diplomats were aware of the attack on Pearl Harbor. Nomura and Kurusu were not fools; they understood the two countries were inching ever close to war. On November 22, the Japanese foreign ministry sent a coded message to the ambassadors that put November 29 as the deadline for any agreement between the US and Japan. You can dig through this page for the full text of the message as well as other messages sent to the diplomats, but here's the pertinent part.

There are reasons beyond your ability to guess why we wanted to settle Japanese-American relations by the 25th, but if within the next three or four days you can finish your conversations with the Americans; if the signing can be completed by the 29th, (let me write it out for you-twenty ninth); if the pertinent notes can be exchanged; if we can get an understanding with Great Britain and the Netherlands; and in short if everything can be finished, we have decided to wait until that date. This time we mean it, that the deadline absolutely cannot be changed. After that things are automatically going to happen. Please take this into your careful consideration and work harder than you ever have before. This, for the present, is for the information of you two Ambassadors alone.

That's about the extent of the knowledge that the Japanese ambassadors had of the attack on Pearl Harbor. The Japanese government would not have informed the diplomats of any precise details of the attack, even believing that their coded communications were secure. It would have been an unnecessary risk. The Japanese diplomats in Washington didn't need to have knowledge of the attack on Pearl Harbor to do their jobs, or for the attack to occur, so they were not told. If they had been told, the Americans would have intercepted the message and been aware that the attack was coming.

In addition to the sources linked above, I've drawn from Gordon Prange's "At Dawn We Slept," and Ian W. Toll's "Pacific Crucible."