Updates:
Had both text chats & Phone chats with AirBnB customer service. NO help - if this alleged $917 of "unclaimed property" is real (again, why can't they just deposit to my bank account on file?) then the AirBnB C/S reps have no ability to either confirm nor deny the validity of this scammy letter. << That point alone is a problem.
I called the number on the letter (starting with *67 to suppress my outbound callerID) 855-888-8749 and a vague, unbranded voice greeting dumped me into a phone queue. Finally a man with a Hispanic accent came on, weirdly asked for no information from the letter to ID me, asked for no other concrete information. Just told me to fill out the letter and return it.
HE ALSO TOLD ME that if I did nothing, the "government would get the money and keep it". Prior to the call I had visited my state's Unclaimed Property website and searched again. Their search mechanics err on the side of returning too many hits, not too few. I saw a PILE of people with my last name with money owed to them. If this mysterious CS rep at 855-888-8749 was correct, then that website either would have been fairly empty of search results or the website would have been non-existent (maybe some friction-ful phone line and major hassles to extract unclaimed property... but nothing like that). He basically was making a claim that all governments are corrupt always and without exception, to stoke fear. I told him flatly our state government was not corrupt like that because I had successful past claims of unclaimed property (factual).
He alluded to some email where I should email about this "unclaimed property" of $917 - again, connected to AirBnB. I asked for that email and he gave me: ENHANCED-CA-DD@SOVOS.com
Sovos is a real, international company and Sovos.com is a real website. No where on that letter is Sovos mentioned, however.
Google "855-888-8749" (with quotes) in Google and nearly nothing comes up. Google "Unclaimed Property Processing Center" (with quotes) allegedly in London KY and nothing comes up. If this supposedly legit organization they sure are hiding in the online world of 2022.