As for no thread deletion message, that's just the way the VB software works. Same thing with post deletes: no message.
OTOH, Mods and Admins
can see where the deleted posts/threads were, and the reason for their deletion (assuming the individual doing the deleting left one). We can also open the deleted thread/post, review it, and even un-delete it, if appropriate (which is
extremely rare).
Under normal circumstances, the poster who got a post/thread deleted would be sent a PM about it - most likely an infraction PM.