Buizel strikes me as similar to Squirtle in some ways. Squirtle never said that it didnt want to evolve but it is very competitive, especially around its evolved form Wartortle. Buizel seems this way as well, i dont see it evolving.
Ash already has a evolved water type, Kingler and the writers need to focus on it. I do think though that Tododile has a good chance at evolving, probably once.