Okay had a similar issue, from when a i read in the Framework FAQ you're supposed to reform a caravan normally, not as a vehicle caravan that was it allows you to toggle the checkmark or X and load pawns into seats

But also no worries if you do, in the world map you go to the pawn tab and simply drag the pawn from where it says dismounted into one of the passenger seats. its a drag and drop feature. As for loading them into the vehicle, you can either do that on the world map or select the vehicle and click on the downed pawn with the "load pawn" button and if you undraft a pawn you can prioritize loading the pawn into vehicle