validity of "loan" written on check memo without an agreement for repayment

I have a former employer who deducted my last paycheck from my back account. I went after him through the labor commissioner's office and they found him liable and forced him to repoay me the amount he took plus penalties. Since that happened he decided to take me to small claims court and say that a partial sign on bonus that I was given was a loan and that I owed him the money back now after a year of working for him. it was a vebal agreement for the sign on bonus which took me weeks to finally get. He did write "loan" in the check memo but since he was a new employer and I didn't want to make waves and there was never any talk of repayment I didn't think twice about it.
There was not an agreement for repayment and the check was never mentioned until after I left and filed against him.

he brought in a photo copy of the check as evidence and that was his only evidence. I said to the judge that he could have photoshoped that document and who can say when or by whom that "loan" was written.

The labor board denied this defense and awarded me a judgement, but the judge did not want to hear that. The judge told me it was irrelevant what the labor board says and that this photocopied check was the only strong proof.

Please help me find something to take back into court as I appeal this decision. I would have thought that no discussion or written agreement of repayment for nearly a year would have been enough evidence on my side...but apparently not.

It would seem the terms of the loan would need to be clear as well.

But we would agree that the word loan on the check is a piece of evidence.

If you could show there was never any attempt to seek payment or collect, that may have some affect??