Obviously, as Justin Roiland’s words in 2019 conveyed, he’s going to be missed, which is likely why the show felt it important to immortalize him in Season 4.
It may even be something that happens again in the future, so if fans see his character lurking in the background of future episodes, they now know why he’s hanging around!
Mendel has been described as one of the producers who has shaped adult animation throughout the past couple decades, so it should come as no surprise he’s worked on two of the best.