Like i said, it’s not trivial. I’ve been doing this for a little bit but i have to admit i’d either have to dig into the code, or inspect the rendering somehow since off the top of my head i don’t know how its done.
What @makc3d suggested seems reasonable. I don’t understand how your 3d model relates to the cubemaps, but for starters i’d try to put them in places where they were generated from. Although these look like photos not 3d renderings.
placement in his shader would be the position of a cubemap. I’d try with two at the same time. You read one projected from point A, and another one from point B. You fade from one to the other as you move from A to B, and coordinate that with fading out the skybox. You can’t move much in a skybox until i stops making sense, i’d do that from like 0 - 0.2 then move in 3d to 0.8 then fade in the other to 1.
Matterport of course has the advantage of the (rough) 3d model corresponding to these cube maps.