just tried it out, and I wasn't able to get it to work.
This is what I tried:
onactivate > player > changedatablock > dragon land
onactivate > player > savedatablock
then ctrl k'd and it reverted me back to the standard playertype/minigame playertype
is it possible that the event doesn't support custom playertypes, or could be an add-on conflict?
I am using blockland glass, if that matters