Their is a new post up at www.tigershockey.com which confirms his invite. It is also confirmed by the The Elk River Star News which was the first one to break the news 6 days ago.
King is expected to attend the annual Travers City prospects tournament which is held directly before NHL Main Camps get underway.
Tristan King goes on to say that he is now 100% healthy from the concussion and groin injuries that plagued his first season as a Medicine Hat Tiger.
In the article it also mentions that Dallas had interest in him before the draft, but didn't know if they should draft him because of a shortened season.
To read the article first hand here is a direct link.
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