I googled, and I could not find any ovens with Teflon in them.
On top of that you have to heat the Teflon over 500F / 260C, and ovens temperatures don't go so high (except in self cleaning but a non-stick oven would not have self cleaning).
I suspect something else happened to your birds - probably simple smoke from food residue, which kills birds much easier than overheated Teflon does.