Which JRemote are you using? JRemote for iOS, JRemote for Android, or JRemote2 for Android?
The easiest way today to do what you want would be to save Playing Now as a Playlist, and then play that Playlist on the local Player Zone. Unfortunately saving a playlist isn't implemented in JRemote2 yet. I don't know about the other versions.
On a PC you could link Zone 1 and Player temporarily, and then unlink them later. Linking may even copy the Playing Now list to the Player Zone, so then you could unlink and stop playback on Zone 1. Try that and see. The linking sequence is important. I got into work once with a non-Player Zone, but it wasn't consistent.
There is no simple "Move the Playing Now list from Zone 1 to the Player Zone and continue playing" function. At least a couple of people have asked for that, or something similar, and particularly from JRemote rather on the PC. So, keep asking.