Is there anyway I can get Blockchain to confirm this?
No, Blockchain.info is just a service. They are not the Bitcoin blockchain nor do they have any power over Bitcoin. Confirmations come from miners and those miners are the only ones who decide whether your transaction goes into the blockchain or not.
What about if they use his account balance history to determine?
To determine what? That he sent the Bitcoin? Sure they might have it in their logs, but nothing can be done about it. For all intents and purposes, the transaction never happened and the entire Bitcoin network doesn't know that such a transaction existed.
Knightdk is correct. You are wasting your time.
And almost every question you ask is not based on how bitcoin works.
Very simply, your friend still owes you 0.35 btc.
Request that your friend send you the remainder of what is owed to you.