It depends on if they unscrewed the valve internals or broke off the valve stem. On large trucks the valve stem is metal and bolted through the wheel so stem breakage requires the wheel to be removed and tire dismounted. This isn't a trivial operation on a large wheel as most shops change large tires by hand.

And, all tires in the bus lot will need to be inspected, who knows if they slightly damaged one just enough to cause a slow leak or punctured a side wall. This could lead to a tire failure / crash while on the road.

This should be a felony charge as there is a huge safety issue here.