So I'm playing the Bach suites and I've got the notes and rhythms down and everything and now I'm onto an intonation issue on the string crossings when they're on the A string.

So you've got the first 3 notes of the first 2 lines: G, D, B, A, B, D, B, D
G, E, C, B, C, E, C, E
G, F^, yada yada
My higher notes squeak so badly up there that I don't think it'll be a superior come solo and ensemble contest like 3wks from now. Any ideas how to eliminate the squeaking there and at the last bit after the chromatic part?

Je peux parler Francais et Anglais

You could try using a mute (not a practice one) and make sure there is not too little or too much rosin on your bow (it goes really squeaky if there is too much). Also, try practicing it really slowly first. hope this helps!