While Timmy III can probably indeed easily afford "one hundred thousand reasons", I wouldn't even put it past him that he is trying to trick Wendell with... play money.
You are correct, the main er "body" of this work wraps up tomorrow, with mop up action happening throughout the first several weeks of January (if that long).
I can't fault Wendell's logic here. Why settle for just killing the asshole when you can get him to pay you a tenth of a million not to, and then do it anyway?
Sure, there was no time for Timmy III to set that up, but the smarter thing to do would have been to arrange it so that Wendell only gets the money afterwards, after leaving with Timmy still being alive...
(Incidentally, there is an idea for a future story in my head where Bettina does something very similar...)
