Similarly to "de-anonymizing account hashes", CSPR.cloud can also "de-anonymize" account purses which can be used as the only transfer source or destination parameter. Let's have a look at transfers that happened in this deploy for example.
Note the to_purse_public_key property that was added in the second response. It contains the public key that corresponds to the account having the to_purse as its main purse. Please check Transfer Optional Properties to learn about all the optional data that can be included in the Transfer API responses.