I was on the wait list last year for about a week before I got the call that I was accepted. There will be several people that are accepted off the waitlist as late as orientation next week because of late acceptances to medical school that free up spots.
Also, I see that you are thinking about getting a second bachelors degree if you do not get into the Med Sci program, but I would advise against this. In my opinion, it would be much more beneficial to study for the MCAT (if necessary) and pursue your plan of working at a clinic or hospital. Clinic hours, volunteer work and developing relationships to get awesome letters of recommendation will do a lot more for your application than a second bachelors degree will (and a lot cheaper!) Good luck!
PS: Don't forget that the UNTHSC Facebook group also includes CRM (Clinical research management) and Biotech students, so there may be a few more spots open than you think.