It wasn't complicated when we were with Tom's Moorings.... one person dealt with the mooring fees and the other paid the licence fee, insurance etc. Seems a perfectly sensible way of splitting the cost of keeping a boat on the canal.
As their mooring form needs a lot of the information that they've already got for the boat registration (name, licence number, length etc) - that would imply that their systems aren't linked together.
As for email - they wrote (snail mail) to my brother and got their own email wrong, so my brother guessed what it was and it then took them more than a week to respond.