We had only underscores and the port number, so Skype_for_business_4443 as the pool address. The pool would not select without the addition of the quotes, which was odd to me, as I had never had to do that before. Figured it was worth mentioning in the event anyone else has the same issue.
Thanks for the info on the asterisk, were not calling anything by port number, so it seemed odd, but makes perfect sense!