It isn't outside the realm of possibility that a team could value Ostapchuk like a 1st round pick. I don't think every team in the league would value him that way, but he has had a decent start to his pro career and he was originally selected 39th overall.
If he wasn't being shopped, but Grier got a deal that he couldn't refuse, then he must be high on Ostapchuk.
It could also be a scenario where he didn't openly shop Zetterlund in order to maintain leverage. It doesn't take a rocket scientist to realize that teams are going to call about him. Maintaining a "I'll listen but I am not shopping him" position puts Grier in the driver's seat. You could argue about creating a market, but we don't know that other teams also didn't call him about Zetterlund, only that he wasn't put out there as available.
If Grier values Ostapchuk like a 1st, I don't think he is getting a higher return in the summer. Is it possible a similar return might be put out there? Maybe. But given that San Jose is not a playoff team, if he identified what he got as Zetterlund's value in the summer, then he might as well pull the trigger now if he doesn't think they can come to terms on a contract.