Cast when damage taken + Rejuv totem

I can't get my rejuvenation totem skill to fire using cast when damage taken. As far as the I can tell from the wikis and searching through the forums it should work. The CWDT is level 4 and should be able to support gems requiring level 44 or lower. The rejuv totem gem is level 12 and requires level 44 to use so I am not sure what I am missing.

Anyone able to tell me what I am doing wrong?

Yeah, you're using a totem, they aren't cast anymore. Totems are placed now, similar to how traps are thrown and that means no trigger gems.