I've been following this thread and I'm really sorry to see the situation you're in. That's a lot of money to watch go down the drain.
Several people have suggested that you immediately consult a lawyer. That's what you should do. If you haven't done that, DO IT NOW.
The first thing the lawyer will ask to see is the contract / purchase order / quote from the vendor. If you don't have these, I'm afraid your legal recourse may be very limited. Chances are the money you sent the vendor is long gone and they may very well be basically insolvent. Some clown going on about being the "CEO" of Rinkydink Inc. and needing to talk to the "owner" is a big, giant red flag. He must have seen "Billions" one time too many. Without a contract of some kind, you may not even be able to prove in court what if anything the vendor agreed to do for you. No court will award you anything - if there's anything to award in the first place.
Anyone thinking of having any OEM knives made, know this: There are very few companies in the world who can make high quality OEM knives or even grind blanks to industrial standards. There's reasons why most OEM knives are made in China or Maniago, Italy. If you're talking to anybody about OEM work be damn sure you get an official, written offer/quote listing exactly what and how they will do for you and what it will cost based on an industrial drawing of the part you provided and when it will be done and delivered. Check their references if it's not a well known company. Then issue a written purchase order referencing their quote and once again listing exactly, exactly what is to be done and including a drawing with 100% instructions. You cannot have too much information. Even with 100% honest vendors, expect something to go wrong or there to be "misunderstandings."
Good luck and I hope you get made whole. Don't under any circumstances confront the vendor in person unless you want to add jail to your list of woes. Or getting shot.