Hello @Liz McCrae,
You say you are "previewing" the registration you go done the same path. Are you actually testing or previewing? That will make a big difference. When testing you can choose your contact type from the settings dropdown.
Did you add the names to an invitation list? If you did each invitation list can be associated with a contact type too, which would send each registrant down the correct path.
It does sound like you associated the contact type with each path in the site designer, but worth double-checking the settings are correct.