Usually, when intentional backdoors like that get found and fixed, the 'someone else' stays silent. Otherwise, they provide proof that they've been planting backdoors, and that's much worse than having a hole plugged.

To get an idea of how this stuff usually works, start with the Simple Sabotage field manual:

https://ia601309.us.archive.org/14/items/Simplesabotage/Simp...

If a government agency wanted to sweep this under the rug, don’t you think they’d just pay the bounties for the guy instead of giving him more ammunition for his crusade?

I think it’s more likely that the guy is just being as abusive to these services as the quotes in the article where he’s talking about crushing their bones

I'm not a BitLocker user or expert, but I thought I'd read that if you used a BitLocker PIN, the exploit didn't work. If the gov't asked MSFT to deploy an exploit, wouldn't they make it work PINlessly?

There's zero proof it's an intentional backdoor, it's just FUD spread by the exploit author which is probably not helping his case and may be reason for his ban.

Microsoft doesn't need to put in a backdoor on disk because they can make payloads that'll pass the TPM and not need a single trace on the disk.