The message you see logged is not an error, it's just an indication the truck doesn't have a crew so, if your problem is just its missing the crew animation, it's not a problem, it's how that truck is made, but the refueling will work.
We confirmed multiple times we are working on a completely new animation made for airplanes not high enough to use the raised platform tankers, which are the only one with a crew, but it's just not there yet. This truck is there temporarily, to prevent the even smaller one to be used, which is what happed before the latest update.
