So while I knew what incidents Ian was referring to here, but I must say, I wasn't 100 percent sure of the answer - I suspected it was possibly conflating two events - and it took awhile to look into! In short, the 26th Cavalry (Philippine Scouts) is known for two actions on the Philippines. One at Morong was a famous cavalry charge - but not against tanks - and the other was a famous delaying action at Binalonan against tanks, but I wasn't sure whether they had ever charged them!

To start, the famous charge came from the 27 men of F Troop, led by Lt. Ed Ramsey, who took on a Japanese brigade in position near the village of Morong on Bataan on January 16, 1942. As noted in the video, they no longer carried sabres in the field, so were armed with M1911s, M1 Garands, and bayonets. This was the last proper cavalry charge of the US Army (I say proper, because Special Forces engaged in mounted warfare in Afghanistan), and despite being outnumbered, it was successful. F Troop pushed back the the Japanese to take the position, and held it long enough to be reinforced by infantry. It wasn't long after that event, the 26th was dismounted, and would finish the fight as infantry. Caring for the horses on meager supplies was too much (the poor fellas were butchered and used to supply meat...). Now... did they charge tanks? Not that I can find. Scanning through a number of sources, I didn't find a single one which mentioned Japanese armor being involved in the engagement, and in any case, while he doesn't name the incident, calling it a delaying action implies the engagement at Binalonan on Dec. 24th.

Checking a few books on the topic - success! Both "The Doomed Horse Soldiers of Bataan: The Incredible Stand of the 26th Cavalry" by Raymond G. Woolfe Jr. and "Twilight Riders: The Last Charge of the 26th Cavalry" by Peter Stevens detail the engagement at Binalonan, and while for the most part fighting was dismounted (and with antitank weapons, I would add), as was typical of cavalry tactics at the time - the horse being more a conveyance than an assault mechanism - there were several points where the American cavalrymen were mounted, and there was at least one very clear point where the cavalry charged, and a few which might imply it. The best case, which at the least satisfy's what we're looking for here, is when A Troop, under Capt. Leland Cramer, undertook a counterattack on the advancing Japanese 2nd Infantry, and while it is unclear whether tanks were with the infantry at the start, they were soon reinforced by them in order to eventually halt the American advance, eventually forcing A Troop to retreat and re-entrench. So in this case, somewhat similar to the Poles in 1939, the Americans hadn't intentionally charged tanks. Rather, they charged infantry and their success eventually took them to where the tanks were, after which they retreated.

Another incident mentioned was with B Troop as the Americans were preparing to pull back. Not exactly a charge, but certainly fearless engagement in an unbalanced situation, Lt. Seymour of B Troop took up the rear guard with another trooper, and attacked a tank with grenades, after which they both hightailed it - by foot - to their nearby horses and galloped off.

So in short, yes, the 26th Cavalry did engage Japanese armor in the Philippines, although it doesn't look like they ever intentionally charged tanks on horseback.