Welcome to Smogon! Take a moment to read the Introduction to Smogon for a run-down on everything Smogon, and make sure you take some time to read the global rules.
I suggest you change roles of Skarmory & Rotom-W
Physically Defensive Rotom-W can take on belly drum azumarill. It has enough speed to our speed Azu, can take take a hit, Will-O-Wisp it cripping it a bit, & then Volt Switch out until something to resist Play Rough or Waterfall in your case...