Need Help Creating a group within the Tokyo Disney App with multiple purchasers

I have searched for answers and tried to get clarification to no avail. If anyone can provide any insight into our situation I would greatly appreciate it. Always happy to clarify if something is not clear.

I have 2 groups going to Tokyo Disney and Disney Sea. We have a group of 4 and a group of 2. One person had purchased on their account the 4 tickets and another person purchased the other 2 tickets on their account. I wanted to know if these two groups can join together within the Tokyo Disney app for purposes such as purchasing premier access passes?

We have attempted to join the 2 groups but were unable to do so. The 4 people are able to join the group through the app, and the 5th person who did not purchase the other 2 tickets are able to join the group, however the person who purchased the 2 tickets on their account are unable to join my group because the app states he's "already apart of another group" when there is no one in his group. So is it not possible for the two purchasers of multiple tickets to join a group together?

If that is the case, is there no way to isolate the 2 tickets on his accounts that way the individuals can join the larger group?