Hi, I've just set up VU Solo2 which does not have RF out. I have a just received a Triax RF modulator (Amazon) which I hope to setup in the next few days to send the signal to the other TVs as I did with Sky. You will have to order spare remote controls for your box to use with each Triax eye. Perhaps some other member has already cracked this.
I'm not sure why you'd need a modulator if the box has an RF out?
Is it to alter the RF channel to something the box can't do?
Anyway
If you have an RF out or you modulate the CVBS signal to an RF signal, you could always use a Global TVLink Plus for the remote operation
tvLINK®plus
https://www.youtube.com/watch?v=TbaF96xKROs