Internships can go a long way with certain programs, but a good NBME goes a long way with all programs. If you don't think you'll ever be able to do well on the test (which anyone who reads my posts knows I believe is a load of horse hockey), then an internship is your best bet imo. I would try to find a 4 year program that has a history of accepting their interns and just working your a$$ off for a year. They might offer you a spot the following year, but at the very least they'll write you good letter of recs.
I think APB's advice about a GPR is definitely something to consider since a GPR will hopefully give you good training if OMFS doesn't work out, while at the same time giving you something to put on your resume that may give you a little advantage over the peeps coming straight outta dental school (and you'll definitely have more time to study in a GPR than an internship). The GPR, however, is really hedging your bets...and some programs may view this as you not committing to the cause.
My advice, find an internship with q4-5ish call and then devote the next 5 months of your life to the CBSE and get a 75+...if you're unwilling to do that, then find an internship that takes their interns.
Hope it works out.