Thanks for looking into this issue.
I did a little more investigating and it seems to occur when the LT-2 strut gets fully compressed. Even on a static, landed craft, if you gradually reduce the spring force, once the landing strut fully compresses it explodes. This doesn’t happened with the LT-1 strut though.
No idea what that means though in terms of the mesh and collision physics...
Incidentally, the fixed landing struts that are included as an extra in Restock don’t suffer this issue so they are actually very impact resistant.