lets assume you are right about Hendricks for the moment. then the 4th line will be mathias copp dano. roslovic has a very small chance of bumping copp but then copp would bump dano. and 4th line would be mathias roslovic copp.
As far as I can tell any of them would be trying out for a 3C scoring role and Lowry would be the shutdown 4C.
If they make it off course. I don't think Mo will put any of Roslovic, Petan or Copp in a limited 4C role. At least I hope he won't this time.
If they can't prove they can handle it then I think Lowry comes in as a shutdown 3C and we see a
Matthias/Tanev - Hendricks/Copp - Copp/Dano
type of 4th line and both Roslovic and Petan with the Moose.