The protocol says, that there are two further scenarios when the secret is successfully recovered:
Unpair new pairings, continue using old ones;
Unpair old pairings, update the new secret, continue using the new ones;
For the second case, we need to know the helpers' old public encryption keys in order to encrypt unpairing messages. There is no way to do that with just the SHA-384 hash of that key, if, for example, the current "new" encryption key is different from the "old" one. Thus I suggest replacing the helper hash with their public encryption key.
The protocol says, that there are two further scenarios when the secret is successfully recovered:
For the second case, we need to know the helpers' old public encryption keys in order to encrypt unpairing messages. There is no way to do that with just the SHA-384 hash of that key, if, for example, the current "new" encryption key is different from the "old" one. Thus I suggest replacing the helper hash with their public encryption key.