Ah yes, that's a picture of one our member's motors
Yes, the awning poles do slide in to the roof, and they are a lot stronger than they look

You can't exactly swing on the end, but they can certainly take the weight of the awning.
On the Carawagon, there are storage 'pockets' along the inside, the full length of each side of the roof, which hide the poles on the inside as well as storage for the hammocks and anything else you want to hide. You can see the pockets here, waiting to be re-hung at each end. Note that this is my Carawagon, and we haven't fitted the awning poles yet.
There is also a top pole which you slot in afterwards, as you surmised.
We've made a set for Patrick's Carawagon, as they were an option and not all had them. Easy enough to make.
We made bosses for the holes where they slide in/out, out of 1" thick plastic (nylon) but plywood would be fine. On the inside, we used plastic waste pipe, the full length of the roof, for the tubes to slide into, and made 3 brackets on each side to support it.
When the poles are out at full stretch, they still need to have a couple of foot inside the roof, and one of the support brackets is positioned at that point to give maximum support.
I'll be making a set for my Carawagon, as again, it wasn't specified when new, so will take pics. of the parts if you want, or if you're really in a hurry, I can take some pics of Patrick's tomorrow
There's a 'not very clear' pic here of two Carawagons, Steve's and Patrick's, back to back, with a tarp over.

This has been our favourite configuration for the las few camps as we can drop the tarp down on either side depending on the wind direction.
Notice there are no support poles, though Steve does have a set for when he uses his purpose-made awning as it is very heavy, good quality, canvas; much heavier than the original Carawagon awning, I think.
HTH,
Robin.