Couple things:
I think this is a simple oversight on relic's part. This level of damage cannot be intentional, including the ability to kill okw trucks.
Second, the jagdtiger was reversing when the smoke came down, and it was not the Katyusha that stunned it, it was the first shell.
Third, if this was indeed intentional, it does not justify having this level of damage in an offmap, saying 'what else are you supposed to use to kill it' means that unless you have this ability you are gimped. That doesn't fly.
