What to do with a wigglytuff with the "dazzling gleam" special attack and the "pound" fast attack?

gym defender

Keep it.

I usually use a team from 1100-1300 range to prestige up a gym. I aim for taking out 3+

Wiggly with that Moveset is a very good and standard choice for my 6th pokemon. It has a fast charge move perfect for finishing off that Low hp whatever that my typed advantage did. It has enough hps that even if in transitition to it I get hit by a high level charged move, I will survive.

I wouldn't power it up, but I would use it for a Prestige Training Team.