Earlier quoted context omitted.
The claims there have been thoroughly debunked, most recently by Mozilla and the European Commission as part of their due diligence, details here: https://bit.ly/35RDKzB
Their Google cert literally is "Tesonet" - how is this claim debunked - you can check it yourself.
There's a historical, almost accidental connection dating back to the infamous November 2015 DDoS against Proton, but zero connection today, and certainly not in the way it has been portrayed by people seeking to attack Proton. Android certs are permanent and can never be changed so that is why there is still one mistakenly issued Android cert out there today.