That response from ChipMixer means nothing. It's definitely not being run from a government office with a ChipMixer signboard. It is more likely being run by Chainalysis and being funded by Governments.
Chainalysis can't be funded by governments because it already had 6 funding rounds with millions of dollars each, and a load of investors willing to throw money at it. Your theory doesn't add up.
Working with governments =/= getting funded by them, unless they awarded them a forensics contract.