The best way to set up an iOS playtest is by directly uploading an IPA file of your game. Everything will just work – PlaytestCloud is a little magical that way :)
Specifically, you don't need to think about collecting UDIDs from players or creating special provisioning profiles when preparing an iOS version for playtesting. We are automatically re-packaging your game for easy and secure distribution using a process that does not require any changes or preparations to be made by you.
You can read more about our process here: https://www.playtestcloud.com/resources/distribution-technology