Well, I am the expert for all things gooey...
Never seen, but just to offer a guess. Like you say, it looks like some form of condensate. Certainly not molten plastic, that appears intact. I could imagine either a (mild) temperature effect due to a higher contact resistance of the connector. Or an effect of electrical fields causing some inductivity which may locally attract some vaporised and somehow charged particles / aerosols, some sort of fogging. But no idea what it is or could be. How does it smell? Is it water soluble?Humi is fully cedar lined?
Apart from that you should stop smoking inside your humidor. 😅
And, yes, do get in touch with Ray @PigFish