Well, just in case you're not being sarcastic, and for the kids in the back who weren't paying attention, let's quote the wiki here... namely, two passages:
A cease and desist letter is a document sent to an individual or business to stop allegedly illegal activity ("cease") and not to restart it ("desist"). The letter may warn that, if the recipient does not discontinue specified conduct, or take certain actions, by deadlines set in the letter, that party, i.e. the letter's recipient, may be sued.
(...)
Cease and desist letters are sometimes used to intimidate recipients and can be "an effective tool used by corporations to chill the critical speech of gripe sites operators".
The C&D is the first step
before litigation. It's the issuer telling the recipient
"yo, stop that shit or I'll sue yo' ass". It's a legal threat. Without actual follow-up (read: DHC pressing a libel lawsuit against Qutens), the C&D has no value whatsoever. That's why I called it the most basic bitch attempt at cowing someone for cheap: it's something a lawyer can bang out by doing the equivalent of filling in a Mad Libs form. It's effective sometimes because people look at the price of the litigation that would ensue if the threat issued by the Cease & Desist letter was carried out and back off.
Qutens, on the other hand, is gearing up to say "bring it!", which puts DHC in an interesting spot. They may well have enough money to sue her pawprint panties off, but the damage to their brand is only going to become more serious, and their clientele is only going to shrink. The thousands of dollars they'd be spending in legal fees may very well not be worth it so silence just one Twitter sped, even more now the document talking about their "alleged" criminal conduct is being shared even more enthusiastically through the fandom.