yeah , Gaz your right the ECS has a large washer to hold it all in place.
The damage looks to be caused by movement which Im guessing we all will get , tony just puts his car through more paces lol
ultimately you need uprated eng mounts and a solid bottom mount.
Stretch bolt should be one time only , but many get away without doing so but its not the way it should be done and carries (some) risk of something going awry.