nostr:nprofile1qqs9phjf9nl9guj9phc6q9m0makezh5hedwelrf7enhh6f0lp2y8rhspz9mhxue69uhkummnw3ezuamfdejj7yxctw3 turns out you were right. from https://docs.cashu.space/faq#mints

> Why can't I receive tokens from one mint into another mint?

> Each mint has their own tokens. Therefore, you cannot receive tokens from one mint into another mint.

> You can, however, use the tokens from one mint and swap them over Lightning for tokens from another mint. To transfer tokens from one mint to another, use the Multimint Swap functionality.