Sounds like another case of the Spacer causing issues again. If you look at it you will see a factory spacer, that is whats causing your Pipe not to sit and mount fully imo.
The way I flixed mine and my friends with the same isssue was to remove that stud with that spacer on it and get a fully threaded bolt to replace it with. For some reason this spacer does not like aftermarket exhust. This was done on my 99 and my friends 01 so if you got that thing on your car chances are its the slut thats screwing ya.
I wouldnt play around with exhust muds, sealers extra gaskets when all your doing is masking the issue imo. Chances are you will be back under there once it fails again. Look to see if you have that spacer ony our Term!
I have a buddy who owns a muffler shop so if you need to get your car on a lift and have it done right for cheap pm me and I will give you his info.