It doesn't matter the price when the loan was originated, because as the affidavit says, Celsius had provided additional capital. When you have an overcollateralized loan, as soon as it goes below the required threshold a capital call goes out, and you liquidate if that's not met. You don't wait until it's at bankruptcy to issue a call.

https://www.ft.com/content/5eff6c38-9410-45af-94f7-2488b3a87... this also confirms some of it:

>“If bitcoin drops, they give us a margin call [and then] we have to give them more bitcoin,” Mashinsky told the FT in October. He said the loans were typically 30 per cent overcollateralised. The price of bitcoin has since dropped by about half to $30,000. The person familiar with the matter said Celsius had indeed posted more collateral as a result of the falling price.

Sure, maybe everyone's lying, including in sworn declarations. Alex has obviously lied a lot leading up to the Celsius bankruptcy, so I'm not going to say that anything he says must be true. But I don't see any particular reason to doubt the claims here that tether's loan was overcollateralized, called, and liquidated with no loss (and in fact they returned excess collateral to Celsius, as per the court document above "preserve the remaining collateral in excess of the value of the loan"). I do think it's unlikely he'd swear to that specific claim under oath if it wasn't true, as he'd have nothing to gain from it?