For my Ford, the manual was very helpful. Taking a look at the fuse box diagram, I was able to remove the fuse for the modem.
Thankfully I was able to verify that the modem power was secured because when I enter the infotainment settings to view the modem serial number, I can no longer see the modem serial number. It is just blank.
This won't work for all vehicles because the modem may have the same fuse as critical equipment.
I'm not sure why people are so quickly disregarding this theory. The Biden administration viewed that both the lab leak and the natural origins were legitimate. He had the US intelligence agencies looking into the origin.
https://www.cnn.com/2021/07/16/politics/biden-intel-review-covid-origins/index.html
Low confidence could just mean there is not much evidence available because the PRC has gone to great lengths to control information regarding the origin.