Biology/Natural Sciences major—transferring into the Big 3

[allvia]

One thing I'm pondering is doing the Bio GRE, hopefully getting a good score, applying to COSC, getting the credits on my transcript, and then transferring the UL ones to TESU. That would take care of two UL courses for about $600 (the GRE test fee + COSC registration and other fees). Unfortunately, the transcript says only "Upper Level Biology, 8 credits," so I don't know if that would work, or they wouldn't count them because of potential overlap with my other ULs.

This won't work - what you're listing here is called Credit Laundering.  TESU (& all the Big3) will require the credit to be sent from the original source; so if TESU doesn't accept the GRE for credit (I don't know if they do or not) it doesn't matter that COSC does.