webdiplomacy.net

Occassionally I click the Draw button when I don't actually want to draw. Against bots draws are sometimes processed immediately, sometimes only after a couple of years, which is a bit unpredictable when not paying attention.
https://webdiplomacy.net/board.php?gameID=355859 (Autumn 1901) should have ended in an elimination (as Austria).
https://webdiplomacy.net/board.php?gameID=359137 would have been a solo-victory (as Russia).
Is it possible to undo such bot draws and resume playing those games?

No, there is no way to un-draw a game, be it with bots or with all humans.
Just for your information, though, the bots response to a draw proposal is not random: they will immediately accept the draw unless one of them a) is leading the board, and b) has gained one or more centres in the past four seasons, in which case they will refuse to draw