I really think this is a pretty hollow threat.
Outside of the insane Khazak 500th aniversary owner (sorry, Sidney, you just missed it by one year) how much could SC realisticly expect to get in Europe - $2M maybe, probably less.
How much can he expect to get eventually in the NHL - $4M, $5M, $6M, ....
The only path to that pot at the end of the rainbow is through the NHL ELS, unless he wants to forgo that big payday for 7 yrs - 25 yo.
You can probably expect the age ranges for the ELS system in a new CBA to be similar to the last one - although the cap may be less and the bonus loophole gone.
First Contract Signing Age / Period Covered by First Contract and Years in the Entry Level System and Subject to Compensation Limits
18-21 - 3 years
22-23 - 2 years
24 - 1 year
25 and older - No required number of years, not in the Entry Level System and not subject to limits on Compensation
So if he wants to wait until he is no longer affected by the ELS, he will have given up 7 yrs - 3 ELS / 2 RFA (no arbitration) / 2 RFA (arbitration eligible). Do you really think his total earnings in Europe over those 7 yrs would be greater than in the NHL (including the 4 RFA yrs)? Not to mention his salary going forward from being a potential NHL super star (as everyone seems to expect) vs being the elusive "Best Player in the World Not Playing in the NHL". And just think what he does to his Salary potential if he goes over to Europe and does not excel - when he's no longer the hot flavor of the month.
And remember, even if he does go and play in Europe for however long, the team that drafted him will still hold his rights as a "defected player", so he will still come back as an RFA with no arbitration rights - not necessarily the key to a big initial payday, especially if you've pissed off that team (and the league in general) in the process.