You shot a deer and let it lay overnight = reasonable

You went out and found it the next day forgetting your tag = reasonable

You "forgot" to validate the tag for a month after the kill = NOT REASONABLE

You should be happy as he!! that you only received a small fine. Working in LE I can tell you that this whole thing sounds quite fishy and the warden made the right call citing you.

Questions that would have been going through my head while speaking with you:

1. I'm responding to a call of "shots fired" in the area and this guy just so happens to have a deer down?

2. This guy admits to not tagging a deer that he killed a month ago. How many other deer did this guy kill and butcher while still keeping his tag "open" to continue hunting?

Honest mistake, maybe. But lots of coincidences. Your wasting your time appealing or anything else. You were guilty of what they cited you for. Consider yourself lucky that your hunting and fishing privileges were not revoked for years and that your fine was not in the thousands. Pay the fine. And hunt responsibly in the future.