Sounds like you're a Disney Engineer.
First, teflon tape is for sealing tapered pipe threads. On a bleeder valve, the sealing comes from the beveled edge of the screw. To me, it sounds like you just wasted your caliper by drilling, and tapping. So now, to bleed your brakes, you have to pull the homemade screw all the way out? Good luck with all you've done, and also remind me never to buy a bike from you.
Edit: Also, not to be a negative Nancy, I'll shit if it does work. Please keep us informed.
Hey, he is 13!! Give him a break at least he is trying to fix it and not expecting his parents to handle it