It shows two options for the exact same move.
Nb5
Only one Knight can move to b5 as the other one is pinned. So Ndb5 and Nb5 are the exact same move.
I think the Openings tab in some cases does have an issue. Explorer does not have the same problem.
https://www.chess.com/explorer?moveList=e4+e5+Nf3+Nc6+d4+exd4+Nxd4+Qh4+Nc3+Bb4+Be2+Qxe4&ply=12
It shows two options for the exact same move.
Nb5
Only one Knight can move to b5 as the other one is pinned. So Ndb5 and Nb5 are the exact same move.