when you use phoenixd then you need to refer to how phoenixd works: https://phoenix.acinq.co/ 
phoenixd writes some data that contains the seed and channel data. 

Alby Hub is just using the phoneixd API - it can not know anything about the seed or similar. That's the same when you use LND. 
In those cases Alby Hub just does API calls to those services. 

I think Phoenixd is a bit different to the phoneix mobile app but I don't know the details. You best need to talk to ACINQ and their support for more clarity. 

We have some scripts to install phoneixd but for support and details about phoenixd one has to talk to acinq.