X11 forwarding from one appvm to another


the reason for this is that I need webex for support team and I don’t want to install it into my appvm (work), where is certain web interface.
So I decided to install webex in separate appvm and forward connection to web through ssh. I created webex appvm, allowed ssh in sys-firewall, inserted pubkey, installed openvpn-server and finally ssh from webex into work with

ssh -XCY user@work_ip

and I’m logged in.
The problem is when I start firefox - it will be started in “work” window instead of “webex”, so if I share screen in webex, the firefox will not be visible.

Is there any trick how to fix it?