That's a thought. Adamski may or may not have known about the German project. In any case, he needed a prop that would look weird if photographed out of context in a clever way. It was 1952, and Photoshop didn't exist, but darkrooms and airbrushes, etc., did. Medical gadgetry would have been a possibility. E.g., here's an incubator designed by a Norwegian firm:
Parts of that thing, especially the lid, could be a start.
George Adamski was a total whackjob, by the way.