tl;dr so essentially we had a vote to decide to print laws in German as well as English and it's possible utopians may have advocated making Greek Latin or French an official language (" considered in the late 18th century to be the languages of God, rationality, and democracy, respectively.") but there would have been nowhere near any sort of majority in support and a vote for that never happened.

I want to step back from the direct question and provide some historical context for the Mulhlenberg legend and the idea people proposed greek as the official language of the US since both are based on actual historical events.

1. greek proposal [The Marquis de Chastellux] (http://en.wikipedia.org/wiki/Fran%C3%A7ois-Jean_de_Chastellux) was one of the liberal french nobles who went to america to support the revolution and was in the Académie française. Serving in Rochambeau's staff (be glad you don't have to read that guy's handwriting) he struck up a personal friendship with washington and in his letters he mentioned some were proposing using Hebrew as the national language

the proposal was, that it should be taught in the schools and made use of in all public acts. We may imagine this project went no farther but we conclude from the mere suggestion that the Americans could not express in a more energetic manner their aversion to the English.

Similarly 19th century american Charles Astor Bristed appears to have made the claim that people were proposing Greek be the American language causing Roger Sherman to make a famous quip (see below)

the best claim for a direct quotation of the work i can find follows:

The American scholar and author Charles Astor Bristed wrote in 1855: “It is still on record that a legislator seriously proposed that the young republic should complete its independence by adopting a different language from that of the mother country, [like] ‘the Greek for instance.’ But this proposition was summarily extinguished by a suggestion of a fellow representative (Roger Sherman of Connecticut, delegate to the Continental Congress and a member of the committee that drafted the Declaration of Independence) that ‘it would be more convenient for us to keep the language as it was, and make the English speak Greek.”

I can't actually find a source before Bristed for the quote or event so it may be apocryphal.

2. the Mulhlenberg legend:

http://www.english.illinois.edu/-people-/faculty/debaron/essays/legend.htm (going to cite a good chunk from this)

In April, 1987, an election judge from Missouri wrote to Ann Landers citing the following excerpt from the local Election Manual to support the argument that everyone's vote counts: “In 1776, one vote gave America the English language instead of German.” The statement is not strictly true, as many of Landers' more alert readers quickly pointed out...On January 13, 1795, Congress considered a proposal, not to give German any official status, but merely to print the federal laws in German as well as English. During the debate, a motion to adjourn failed by one vote. The final vote rejecting the translation of federal laws, which took place one month later, is not recorded. The translation proposal itself originated as a petition to Congress on March 20, 1794, from a group of Germans living in Augusta, Virginia. ...the Aurora Gazette[:] “A great variety of plans were proposed, but none that seemed to meet the general sense of the House” (22 January, 1795, p. 3). A vote to adjourn and sit again on the recommendation failed, 42 to 41, but there is no reason to believe from this close vote that more than token support existed for publishing the laws in German. The vote to adjourn seems to have been interpreted by the House as a vote of no confidence both in the committee's recommendation to translate the laws and in its recommendation on the distribution of the sets of laws once they were published in English...if sentiment on the issue in Congress was anything like sentiment in Pennsylvania, translation was probably opposed by a substantial majority of the representatives... One month later, on February 16, 1795, the House once again considered the question... This time some of the actual debate has been preserved [see site] The January vote on adjournment is sometimes known as “the Muhlenberg Vote,” after the Speaker of the House of Representatives, Pennsylvania's Frederick Augustus Muhlenberg, a Federalist who spoke German with difficulty, so it is claimed, and who was at any rate a member of a prominent family of assimilated Germans...tradition has it that Muhlenberg stepped down to cast the deciding negative, thereby dooming German in America to minority-language status [but we don't have the roll call]... Nonetheless, Muhlenberg was blamed for selling out German language interests by Franz Lher, whose 1847 History and Achievements of the Germans in America presents a garbled though frequently cited account of what is supposed to have happened. Lher places the crucial language vote not in the U.S. Congress, but in the Pennsylvania legislature, over which Muhlenberg had earlier presided. ... However, Muhlenberg later did manage to irritate his German constituents by casting the deciding vote in favor of the Jay Treaty during the Fourth Congress, a move which drove his brother-in-law to stab him and which cost him the next election in 1796. This significant tie-breaker soon became confused with the earlier adjournment cliff-hanger, conveniently fleshing out the myth of the German vote (Feer 1952, 401).

the bold portion highlights where i think Ben Franklin got brought into this false narrative. A game of telephone caused Franklin, a figure everyone still knows, to replace a now obscure Pennsylvanian.