Here is what I found on-line (not sure if this will help):
"34-04 Deluxe panel no communication to Bobcat controllerCode 34-04 occurs when the Bobcat Controller looses communication with Deluxe Display Panel. The Bobcat controller communicates with Deluxe Panel via the System Rx(receive) wire 9220 and the System Tx(transmit) wire 9120. A code 34-04 could also occur when changing from a Deluxe Display Panel to a Standard Panel.Note: The Deluxe Panel will display a D to B symbol in the lower left corner if the communication loss is on the Rx wire from the Deluxe Panel to the Bobcat Controller. It will display a B to D symbol if the communication loss is on the Tx wire from the Bobcat Controller to the Deluxe Panel.Possible Causes
anel switched from Deluxe to Standard with out downgrade procedure being done.Open circuit or short to ground condition on wire 9120 or 9220.Deluxe Panel disconnected.Check the wiring harness and connector pins to the display panel for damage. Test for power and grounds for the controller. This is a loss of communication with the controller."
Did you try to do the downgrade procedure when you replaced the right hand panel? Here is a video:
If both panels are not working, then there may be a short in the wiring between the panel and the controller.
Isoscell.com does repairs on these panels. They have a YouTube channel that shows a repair for code 34-04, but their videos don't really help DIYers.