Previously Paired Magic Trackpad 2 not pairing with new computer

I have a Magic Trackpad 2 that I bought used. I've gone through the steps to pair it with my Mac (plug in lightning cable, device gets added to list in bluetooth settings). I can even rename the trackpad. However, when I unplug the cable, it no longer works. One clue is when it is connected via the cable I get a system notice that the trackpad is connected wirelessly (it is not) and in the bluetooth pulldown at the top of the screen shows the device in blue, but grayed out. When connected it works normally, when unconnected is shows it is not connected in the bluetooth menu. I've tried forgetting the device and re-adding it (several times), renaming the device when connected via cable (was able to do that), plugging it in a different computer (my laptop) and get the same results. I think what is happening is the trackpad still thinks it is paired with the previous computer. Is there a way to fix this - on the old trackpad you could force it into wireless pairing mode. This one does not have that. I unplug the trackpad, it is grayed out, and the connect button doesn't connect the trackpad. Am I out of luck?