Thanks for the tips everyone. Agreed that the offset is probably
compensation for a screw-up.

I never considered doubling up on the wax ring. I'll do that. So I
just stack one on top of another? Any risk that it will deform into
the water path when seating the toilet and disrupt flushing?

No you wont have problem but what do I know I'm just a plumber. Good Luck
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