If your parents can afford it, turning down PLME for UNC seems pretty foolish to me. If you got into PLME, I don’t really doubt your ability to get into med school later on, but that’s the argument I use when someone is deciding between a combined program at a lesser school (or an accelerated program) vs UG only at a top school (or just a school they like better but with no MD guarantee). Unless you actually prefer UNC-CH over Brown for UG or you’re financially crippling yourself by going to Brown (“free money” isn’t really the issue here, the issue is what can you afford), it just seems weird to turn down arguably the best BA/MD program in the country to attend a state school honors college with no guarantee of med school.
I also can’t imagine wanting to be pre-med somewhere other than brown: http://talk.collegeconfidential.com/brown-university/1284648-brown-is-the-best-place-to-be-a-pre-med-p1.html
Also, why do you have 2 days to decide? I thought may 1st was the deadline for schools?