It seemed wrong that any person invited by the initiator (as they started the group ride) could not join as a participant unless they also were separately sent a code through non-mra channels (whatsapp etc).

A person invited during the creation of the group ride receives a notification and gets to see the ride listed in "live now", but that only gives them the ability to view (not to become a participant).
It is as though the (on creation) invite to the group ride is being sent as a invite to a "share my ride". Is this as intended?

Surely people selected to be part of a group ride on creation should be able to become a participant without also being sent another separate invite outside of MRA.