Hey Dude,
Still putting my own system together but also am carrying a Yeti 500X to complement 200W on the roof and a 100W foldable panel. I think this should be fine if the open circuit of your array does not exceed the Yeti's 12-22V input limit. But if you're not into the whole brevity thing...
Since I have a similar setup, my first thoughts were that could be easiest just to run the Goal Zero vehicle charger off the camper's existing 12v port if my camper batteries were mostly topped off and I wanted to link my camper and solar systems. I believe my 12v port has a 10a fuse and I'll try using
this charger on 5a mode. For me the Yeti and car chargers were gifts, so I'm thinking it can't hurt to carry the unit for flexibility especially before I add a DC-DC charger for the camper setup.
For the Yeti500X, I'm having to use a 19v step-down module from my cheap portable panel because the unit won't accept a charge over 12-22V, so based on my understanding wiring in to your camper array could be annoying if your array exceeds that open circuit voltage.
Otherwise, since the Yeti already has its own built-in Charge Controller I don't see a problem maybe adding MC4 connectors before the Victron controller to disconnect the roof solar setup from the camper and re-direct to the Yeti as needed!
This MC4 to 8mm connector from iGreely seems like it'd work, although could be good idea to double-check polarity from the roof. An added benefit would be we can use these MC4's to wire in our portable panels to the Victron controller>camper batteries, say, if we're parked in complete shade and want to put the portable in the sun (if you're like me and don't already have an external separate port).
Looking ahead, seems fine to wire multiple charge controllers to the same battery. I might upgrade my 100/20 Victron unit to the 30 if I add another 200W panel up top and keep the 100/20 to use with an external port and a dedicated portable panel or to avoid having to wire differently sized panels to the same controller. But this is all just like my opinion, man, so curious what you('ve) end(ed) up running and how it works!