LOL
I don't think wise to change the engine because an accessory belt gave up! But you are correct, the cause is not yet confirmed so the fix may not solve the problem.
I requested for an extractor spare parts kit. It is what they supplied along with a comment stating they suspect the cause to be an over-pressure round.
Frankly I have doubt an over-pressure round was the cause, at least I did not feel it IF it is what happened.
The new 4 parts from the extractor kit are now fitted to the bolt, I just need to find time to hit the range and put the gun to the test.
Should it reoccur, then I will get back to Wolverine/B&T for a more in-depth investigation.
Swiss are not known to produce poor designs and quality but yes, some faulty/OOS parts do sometimes make it through quality systems. We will find out soon enough.