After thinking about it for a while, Wally could just decide that the possibility of becoming a speedster superhero isn’t worth going to a supervillain and asking for a favor.
Wally might not be so incredibly eager that he would make a deal with Doctor Alchemy.
There are too many variables in play with a mysterious villain and a new timeline for Wally to be sure that his transformation into a meta would work as well as it did during Flashpoint.
That said, Wally is clearly a smart kid when he’s not leaping in front of cars in the hopes of waking up superpowers that he may not actually have, and Joe made the point that there are ways to become a hero that don’t involve a friction-proof suit and constant jones for energy bars.