if it turns over by hand no problems as far as im aware it should be ok, but would be best to check compression as will has said.
lucky they just bend, ive been doing a crankshaft ladder at work this last few days on a 4.2 supercharged v8, had the chains off it to remove the ladder and had all 4 cams locked up in place as per workshop manual said, and as per the manual i rotated the crank when id done the ladder with the cams still locked up using a 1/2" ratchet no longer than 8" long i proceded to turn the crank, heard a tiny tiny clink and thought oh fuck.
silly be was in 4 cylinder engine mode in my brain so forgot that a AJ v8 cant have a "safe mode" when doing timing as a valve of some sort will always be open, well low an behold ive snapped a valve clean off, with so little force i was amazed. gonna put new valves in but depends on how much damage has been caused. workshop controller wasnt best pleased though as bare engine compleate is £3500 to buy + gaskets etc + labour to fit the bastard back in
was not a good day so if your brothers is ok tell him he is very very lucky.