For what it's worth, the "air conditioner" is just a giant radiator. From the linked bilibili video it's clear (at 1:20 mark) that they've repurposed the radiator, fan, and case from an air conditioner but there is no compressor.
My calculations show that they should have a working compressor to achieve the reported 20C constant under load
To get a video card during lockdown someone gave me an invite to a micro center fan discord where people would post timely photos of what was on the shelves. They would also post photos of their crazy hardware, one of which was an air conditioner duct window insert feeding outdoor air to cool the GPUs (mining rig) and exhausting the hot air into a grow tent.
I've read about this exact practice in one form or another since the Pentium 3 (sometimes just directly cooling with R134).