Adding non- Holley CAN devices to Holley Dominator CAN Network

Im using a PMU 16 and MSEL Solid State Battery Isolator with a holley dominator ECU connected to a Holley Pro Dash. The dominator harness has a pre terminated CAN connection that connects to the pro dash and has a y connector to connect to other CAN devices. The wiring diagram for the holley harness shows 4 wires to the CAN connection 1. 12v switched input, CAN HI,CAN LO, EST GROUND OUT (not sure what that means). There is also a CAN HI 2 and CAN LO 2 on the J3 connector of the ECU. The wiring for the PMU and battery isolator only show CAN HI and CAN LO connections.

Question 1: Can i wire PMU and battery iso to the same CAN connections as the pro dash? If so do i just wire the CAN HI and CAN LO and ignore the power and ground connection?

Question 2: If the CAN bus connection to the prodash cant be used can i use the CAN 2 connections on J3? If so same question on what wires need connected.

Update: Confirmed with ECU Masters the PMU 16 will work with the dominator using CAN2 on the J3 connector and setting the CAN2 to RACEPAK. Spoke to MSEL they were about useless so still need to figure that out.