I see this problem a lot with OTs.

you DO NOT have to provoke or Tomahawk Spiny during start of Tornado phase. Anybody can have Spiny, just make sure you provoke it whenever it generates 2 stacks on anybody.

TAKE NOTE whether you take spiny Early or Later on, you may be royally screwed if Spiny goes to a healer as they have no choice but to produce enmity. ALSO, note that using Bloodbath, Thrill of Battle, Inner Beast, or anything that Generates HP when spiny switch is happening will make it harder to provoke and keep.