I am Facebook friends with Steve Purcell and was chatting with him recently and posed a question similar to this one:
Me: By the way, I've been wondering, is the end of the third season canonical or is it possible that we could still see Max X, or the original Max in any future comics you may release?
Steve: There's no such thing as canon in Sam & Max world. Max is Max in my mind.
You guys have nothing to worry about.
Randy and Mardelle, if you can hear me, I hope heaven is as beautiful as they say