Even if he is for real, I admire him. Sure if someone wants it so much and clearly this guy really does want it so much, then you have to take risks to get rewarded.
Many upon many of top pros wanted and dreamed of playing for a living and they like OP did these sort of things, if not even worse.
Phil Ivey springs to mind more than anyone, wasn't he at some stage I heard him saying in an interview he moved to las vegas
with pretty much nothing, trying to play poker for a living and kept busting and busting till the point he couldn't even afford his rent and had to sleep under a bridge? He then hit that big score of 90k and "never looked back" as they say (I hate that saying by the way"!!!!)
I say if you have the drive and motivation and can afford to lose this money, which you say is your life retirement savings then maybe not but who are we to judge. The point is though, I think with 15k, I'm not sure if live is the way too go in a sense these days. Sure mix and play both live and mix in some online too, you say you have a 12th place in the Sunday million so you have something, unless you got lucky all the way! The amount of hands you get in is going to be so little compared to online. Why not give online a go first? I know it's much tougher competion but I'm sure if you have an edge you will turn a profit regardless.
Good luck either.