Hello Wil.
I agree that yes I too find it suspicious that no photos where taken.
I also agree that if it my engine I would also have it checked by second party.
Here's a different pic of a Teflon valve seal I was refuring to that I think matches joeys debree pic.
The red arrows pointing to 3 parts of the retaining clip that all seam to match.
I have seen this type of valve seal clip get damaged by not using correct dia install bushing tool
or forced onto oversized valve guides causing the Teflon bushing to crack.
As Wil has said. At the end of the day where all her to help in finding the cause of the problem
so as to help educate everyone in knowing what to look for in order to avoid these problems.
Best regards
Carmine