MoCA Connection in 2nd Room

I am having trouble setting up a MoCA connection and Wireless Access Point in my home. The WAP uses an ethernet connection therefore I am working to use a MoCA adapter to get a connection. There are only coax drops in my home, and I am attempting to boost my signal for consistent coverage.

MoCA Adapter I've used https://www.amazon.com/dp/B08ML634YB?ref=ppx_yo2ov_dt_b_fed_asin_title

Current Issues

• The only time the MoCA adapter has a light on for a coax connection is when both the adapter and router/modem are connected to one coax wall output via a splitter.
• When plugging in ETH from the MoCA adapter to the router, it crashes and immediately comes back online when the ETH cable is unplugged
• MoCA is currently enabled in network settings, when turned off the light will go off on the adapter

Methods Tried

• Tested splitter with MoCA adapter & router/modem at both coax outputs, working functionally
• Tested both MoCA adapters and both work functionally
• Tested with no splitter and only router/modem at one output, and splitter/no splitter at the other with the MoCA adapter

I am out of ideas on how to get the connection working, and any help would be appreciated.