The fact that Pawel was able to copy their source code and paste it into an Orca fork is direct proof from Pawel himself that they are honoring the AGPL.
The C&D presumably wanted him to remove the ID/version string or at least stop distributing it, i.e., they only want real BambuStudio on their cloud and that was the laziest way to achieve that
AGPL does not have a "don't be an asshole" clause
"Abusing" is not synonymous with "violating."
If we sign a contract that says you're allowed to park in my driveway in exchange for $10, then I threaten to sue you for parking in my driveway, technically I'm not violating our contract. It's not an issue until I actually sue. But I'm still abusing our contract by threatening you for doing something I explicitly allowed you to do.
Likewise, Bambu was able to benefit by forking and distributing AGPL software in exchange for giving everyone a license to do the same for their fork. Then they turned around and threatened legal action against someone for doing what they previously said was allowed. This may not technically be a violation but it's definitely abuse.
Pawel still has access to the Bambu-modified software, which is what the AGPL covers. There is no violation there.
Bambu's issue is with him taking a fork of Orca and spoofing some data (from THEIR FREELY AVAILABLE SOURCE CODE) to appear as Bambustudio to their servers.
A contract that says you can park in my driveway doesn't give you permission to access my garage and use all my tools.
Absolutely a dick move but not really not abuse of a contract.