Hi. There is no doubt that it is the Janos Hunyadi denarius. The top photo needs to be rotated. The problem is the legend. Your coin shows: M-REGNI-VNGARIE on the reverse, the second part of the inscription IOHANIS. At least that's how I read it. I looked through the Huszar catalog and didn't find one with such a legend. However, I found professional auctions where there is a coin with a legend like your coin. Professionals described it as Huszar 618, but the legend on 618 is M-REGNI-VNGARIE/TEMPORE-IO.GVBER. Maybe this is a variety that has not yet been included in the Huszar catalogue. Below are links to the auction