Filter looks like this:

Both users are members of the Group Service Point, both users have the same role.

A sees 104 tickets, B sees 107.

A can access the three unseen tickets by ticketID no problem.

I also have access to this site/group and I also see 107 tickets.

If we assign any of the three tickets to A, they don't see them under My Pending filter either.

Its the same in both Firefox and Edge, even with removing Cache.