Can Access Seekers separately acquire domestic connectivity services to connect to submarine cables and satellite earth stations?

Yes.  Access Seekers have a range of alternatives to connect to submarine cables or satellite earth stations.  An Access Seeker may acquire a backhaul service from an Access Provider or self-provide the backhaul link to the submarine cable landing 

station or satellite earth station.  Further, an Access Seeker may individually acquire Network Co-location Service at the submarine cable landing station or satellite earth station and, if separately required by the Access Seeker, a connection service onto the submarine cable.