I have a Fox 3.2 on my AW Edge 540 and recently I was flying the plane and one of the muffler bolts came out and the muffler got loose.

My question is:
The bolt that went through the muffler and into the engine to keep the muffler on didn't go very far into the threads on the engine. Either there were not enough threads where the bolt went in or the threads there were stripped somehow. Now, what do I do from here? Can I retap the threads to a larger size...retap them farther...? I will try to get pictures within the next few days if needed.
Thanks a million