Internal medicine is not very DO friendly. Acgme IM PDs have always favored IMGs over DOs. Its not hard to match internal medicine somewhere as a DO, but matching somewhere good, like a mid-tier university program, can be difficult as a DO.
Moreover, the southeast is not DO friendly. Some places in the southeast, like VCU, west virgina U, Georgia university, university of south Carolina, wake forest and muiltiple places in florida, do take DOs. It's uncommon for UNC, duke, Virginia univ, or Emory to take DOs.
Also, I'm not sure what programs you looked at, but if they are only filled with IMGs, you wouldn't want to go there anyway.
Keep in mind you can always move back to the southeast after completing your residency elsewhere.
Finally, I think the whole "IMGs being pushed out" is wishful thinking. Many IMGs are better residents/applicants than US grads. It is, however, too early to see any new trends. It's going to a few more years before the residency crunch happens...if it even happens.