Does MoCA work if we use our own modem?

Wow my house box/enclosure is a mess inside haha... Just had a zip tie on it I snipped off to look inside. it has a 3 way splitter and a MoCA filter that isn't actually attached to anything on the other end. So it has the main line coming in and then off that splitter the newer main line goes up the side of the house and through the ceiling into a bedroom upstairs where the modem and router are. That appears to be the only connected active line I have right now.