I believe it can, but this is 100% not the case.
if no there is no one with the chain online, and some new, fresh client mine a new blockchain - it would be done.
not shure how would react to confrontation with old blockchain, but i guess 51% is the answer -
stronger one would take over, not the higher one. so propably the fresh one.
its not the case here - this is an very old blockchain.
and i can see 2 posibilities:
1 it IS the 51% killed blockchain, why not?
just containing some attacker forced transactions like send all coins to oblivion or smth.
2 somebody took old backup, and waited for fresh clients
to determine which - blockchain need to be explored and find out if there are some weird transactions at the time of attack.
I didn't even looked at the code, or white paper, so its just my wild speculation , I can be really wrong.
but there is smth wrong with my wild guesses, they are correct way to many times.