Sometimes, I wonder how right you might be, but I suspect it has more to do with some folks on rejectionator duty taking tattles at face value, with little research, and others dig a little more (and thus, allow a little bit more). Either way, I just try to adjust and move on.
This time, I *did* have a second version ready, just in case, though I hated having to add the text. I like both, but I like the subtlety of not explaining a joke.
FWIW, I got the concept based off the title, but I've never seen a plasma globe that looks like that. It doesn't read to me as mad science related but "Eye of Sauron with a green eye" (something I'm not sure we could even run.) I appreciate you're going for subtlety, but the connection is just too subtle without supporting text.