The filing, made by Andrew G. Dietderich of Sullivan & Cromwell, the law firm representing the FTX group, said that Alameda is a “substantial shareholder” of Voyager. Under a rescue plan made in June, Alameda offered the collapsing Voyager $200 million and 15,000 bitcoins (BTC), of which $75 million in stablecoins still outstanding as of the date of bankruptcy, the filing said.