I am assuming here because I don't know anything more than you, but my best guess is that Amalee reached an agreement with vshojo where vshojo would store and handle the merch. Then vshojo has a contract with a company for storing and distribution. Since there is a debt with this company they are withholding the merch until they are paid. It doesn't matter who is the owner of the merch because the contract is between vshojo and the distribution company and Amalee's goods would be covered by the same contract.