Lyszczarczyk just finished playing with Poland at the U18 Division IIA in Romania. Poland dominated this tournament, averaging more than 8 goals per game (second-place Romania still has a game left, but was at 5 per game), while only allowing 8 goals against total. Lyszcarczyk himself finished in a tie for first in scoring (with two other Polish players), with 12 points (2 goals, 10 assists). And reports from people watching the games were that, at least initially, he started on the second line for Poland; not sure if he stayed there the entire tournament, as I didn't get a chance to watch, but its possible.
Granted it probably doesn't to anything for his draft position to beat up on teams from Croatia and Romania, and anything less than finishing first in scoring would probably be bad for Lyszczarczyk. However this tournament does tie him to Poland internationally now (unless he wants to skip the next four years), and he is apparently on the entry list for Poland at the senior World Championship Division IA tournament that starts in a couple weeks. Now whether he is on the final roster or not is a different question, but if he does play there it may certainly help him out.