AHC: At least one military engagement in the Antarctic

Due to its very low human population and relatively recent official discovery, the Antarctic has never had any known military engagements. However, there was and still is military activity in Antarctica itself, along with on nearby islands and the surrounding oceans. So while it's unlikely that there would ever be fighting on or near the continent, it's not impossible, moreso before the Antarctic Treaty came into effect.

Your challenge is simple: have there be at least one military engagement in the Antarctic.

P.S. I put this in Before 1900 because military activity in the Antarctic technically dates all the way back to James Cook's second voyage.
I would think your best bet would be a commerce raider during the Napoleonic or world wars using an Antarctic route to avoid the Royal Navy?
Operation Highjump finds that secret Nazi base, whose occupants had not yet heard that the war was over :)
(oops, sorry.... post-1900.... or ASB :p)
My only guess is maybe have the British engage an Argentinian ship south of South Georgia. Why one would be further south is beyond me but, it’s certainly not impossible given South Georgia’s proximity to Antarctica.
Chile or Argentina claim the continent in the 1890s during the height of their rivalry? Leading to a war where Chile or Argentina attack the others bases on the continent?
By giving the Yaghan greater seafaring skills and a toolkit suited for surviving the harsh environment several millennia into the past, you could have them populate the Antarctic peninsula, and on occasion, despite the population densities being absurdly low, tribal clashes and wars break out over hunting grounds, sacred sites, etc... Or the genocide that will happen to them once European contact happens, but I don't think that would really count.
Here's a scenario for TWO battles. Let's imagine New Swabia gets more investment and a temporary whaling station is established. Allies believe this station is helping resupply and coordinate U-Boat operations and is much larger than it actually is. They send over a ship loaded with commandos to dismantle the station, but it turns out they arrive on the same day a U-Boat is in the area. A small battle breaks out in which the Allied ship is torpedoed and sank and the crew captured thanks to quick thinking/sheer luck from the U-Boat captain. To evict the Nazis from Antarctica, rescue the crew, and avenge the defeat, a small flotilla is assembled to capture the whaling base.

Unfortunately by this time, the whaling base has been dismantled and its crew and prisoners removed to Germany, but the Germans keep a wolfpack in waiting in the area. A skirmish breaks out resulting in damage to one Allied ship and the sinking of a U-Boat before the remaining U-Boats retreat. As for the "occupation" of the base, one soldier slips on ice and winds up permanently invalidated while another dies of frostbite after finding some schnapps left behind, but the Allies quickly discover their mistake and avoid an incident like the invasion of Kiska. Some intelligence officers are quietly reassigned for their failure. Nazi propaganda laughs at the Allied failure while future generations of wehraboos use the battle as evidence of the godlike superiority of the U-Boat arm and exaggerate the base into an Antarctic fortress of fascism that surely would've swept the Allies from the entire southern hemisphere in time had Hitler not devoted resources elsewhere.
My only guess is maybe have the British engage an Argentinian ship south of South Georgia. Why one would be further south is beyond me but, it’s certainly not impossible given South Georgia’s proximity to Antarctica.
Argentina has claimed King George Island since the 1940's. If Britain still has a small outpost there during the Falkland's War I could see Argentina sending a ship there.
Here’s my take:

After a devastating nuclear war in 1983, the Pacto de libertad de las naciones americanas (Lead by south American nations), Wêreld Ontwikkelingsgemeenskap (Lead by apartheid South Africa) and the Forum of Nations (Led by the Australasian Commonwealth, who are a monarchy by the way) scrambles for the territory of pre-nuke powers in Antarctica. Fast forward to 2040, world war 4 breaks out between the three great powers of the south. Some fighting happens in Antarctica. It doesn’t mater who wins this war, the fact is that some fighting does occur in Antarctica.