Override site’s registration restriction on accepting invite

We have a custom module that uses the invite module to send invitation to non users. Our site is set to allow registration only by administrator to avoid spam. When the invitees accept the invite they cannot register as its not allowed by the site. Is there a way to override registration restriction when invitees try to register?

We are looking into duplicating registration form on another route then routing the invitees to register there instead of default route.

Any other suggestions to handle this situation?