The person who originally sent the broken transactions deleted his wallet
Sigh... why delete a wallet instead of moving it aside and keeping the old copy just in case?
You should never delete a wallet.For sure he has a backup. Somewhere...
Probably, but if he died without telling anyone about it, then they may have been deleted or destroyed by whomever gained control of his things.
it could also be that his backup is screwed too, witouth necessarily being deleted
btw the only reason for not deleting a wallet tha you know could not receive any transaction, would be hoping in a chance of collision
Of course there is always the possibility that his wallets were corrupted but I think he'd have the brains to have several back ups and maybe even write the private keys down somewhere. At least I hope he did.