Sounds like a super-easy fix to me. Drill/tap/use larger fasteners with greater thread engagement. Should it be on the end-user to fix problems like this? No. But is having to think on your feet and come up with custom solutions common in the aftermarket/modding community? Absolutely. And if it flows well and evenly, I'll gladly do so. I will say this: it's too pricey to have issues like that, though. It's pricey regardless.
Unless you plan on adding material to the flange on both sides you arent going to get a good thread engagement and the larger fastener would only increase the likelyhood of over tightening.
There isnt enough material at the junction to create a strong seal.
Dustin is the only person who fixed his and that was by welding it shut.