Generally, the reason for Grid, Healbot, OpenRDX or Vuhdo is because we are not on the healer toon(s), but want the healer toon(s) to heal.

The top frame is the current character, for each respective window.
That means the bottom characters (in the party section) is different on every account.

The repeater region sends the mouse click to precisely the same position on the recipients screen.
So when you click on a given frame on your master/tank account.
It is not necessarily the same character, even if it is the frame in the same position.

If you could order your Xperl frames, so the entire party was alphabetically sorted, including the active character, then this would work. As in, get rid of the Player Frame entirely. Then include the Player Frame in the Party Frames, and sort all five alphabetically on all five clients.

It's generally easier to do this with Grid + Grid Custom Layouts, Healbot, OpenRDX or Vuhdo.