Short info:
Dji is acting as expected, I enquired again this evening and they are sending me new batteries and a new charging case. I can then dispose of the defective ones...
But I haven't got it in writing yet... more information will follow.
Definitely no moisture, I had unexpected good weather in the northern part of Norway, I fly only in acceptable conditions. The batteries have leaked, what you see there is electrolyte from the battery, i.e. a defect!
Why? I have no idea.
I got my Creator Combo kit from Adorama back in June but ordered all my spare batteries from this guy, simply mind boggling shipping and handling speeds.
I just went ahead and bought the basic M4P kit from him to have as a backup so time to...
The latter. Mine arrived completely unopened and was a breeze to register. NO PROBLEM! I got mine here:
eBay Seller:
102_store
Greensun21
T-909 Poongrim I-won Plus
170 Seohyeon-ro, Bundang-gu,
Seongnam, 13590
KR
They were all over it...