hey. i'm sucky at interviews, i have no empathy for section 2 of umat, and i would NEVER dream of getting a uai of 99+. But, still i'm trying for medicine. I know that the best uai i can possibly get if i work my absolute hardest from now on is 90-95, but with that uai, i still have a chance, though slight, of getting into undergrad med. So, you should take that chance too.
Or, you could try transferring from your uni course into med. That's what i'll try to do if i don't get in. I personally think it would be far easier to try to transfer, because you can try every year, you only need to resit/sit the umat (which, i think, is easier than the gamsat), and with interviews you just need a little confidence practise. The earlier, the better, i reckon.
well, whatever you choose, good luck. ^_^