You don't deal with me in any case, you deal directly with the OTC Address. As for proof of legitimacy, you can use this official link https://www.binance.com/en/vip-portal/OTC-trading-platform?ref=OTC-Spot, to contact the support to backcheck the Binance Enterprise ID used as OTC. I will be happy to provide it to anyone to who wants to check it by themselves.

Procedures are pretty straight forward.

You sent the amount you wish to be swapped to the OTC Address.
The OTC Address sends back the amount -2% of the token you wish to acquire.