Being a neighboring state of MO probably makes Siena/AMC harder for you location-wise. However, you will have breathing room in a 4+4 Siena/AMC program when compared to a 2+4 UMKC program. GPA and MCAT requirements for both the programs seem easy enough. Do wait to see your final cost for each of these programs.
Also, see the poster in the below link from a previous student, vastax105-