Just leave the poor guy alone.
If he's worked for you as a "helper" for 6 yrs, and is offering to pay for this little mistake, you better just count your blessings. Fix it and carry on.
I went berserk once and beat the ceiling out of a finishedkitchen. I was in the attic above(exhale to pass between the roof rafters and the joists, and I'm claustro).
It took 1/2 hr. to get to where I was, about a minute to get out.
(Yes, I patched the ceiling, but my boss paid me for the time to fix it.)