In a documentary about them putting Dwarf Fortress on Steam Tarn talked about how he had to split the $7 million first payment from Steam with his brother and it turned out the easiest way was to just use the bank app.
You are thinking of the NoClip documentary! It is fantastic and well worth your time.
https://www.youtube.com/watch?v=RwLSgaYPKA0&list=PL-THgg8Qnv...
The noclip documentary series for any other readers who might be interested
1. The Origins of Dwarf Fortress: https://youtu.be/MxV24so-dw8
2. How Dwarf Fortress Evolved over 16 Years of Development: https://youtu.be/PiNeDarPzeI
3. How Dwarf Fortress Coming to Steam Changed Everything: https://youtu.be/TX65XCk2-6U anecdote about the money starts @ 18:40
4. Life After the Success of Dwarf Fortress: https://youtu.be/I5zgBXp4e8A