Yeah I forgot about him. We’ll just have to see how he does. Not many 30+ year old euro/Russian players are able to make an impact at the NHL level. He’ll get a look. But, I think Brisson and Dorofeyev are ahead in the depth chart.
Kolesar isn’t going anywhere at $1.4 mil. He had a good year as well.
Kolesar is not a third liner. He hits, fights(though he's average at it and doesn't fight quite as often as the others of his ilk), and can block a shot. Not really good defensively, and his only offensive trait is getting himself open. Funny thing is that as a prospect he was viewed as a goalscorer, but he's, well, not. Kind of a worse Ryan Reaves.
Vegas likes paying 4th liners money with term(an example on the roster is Carrier got the same contract plus a year).
Amadio makes more sense in a top 9 role as he's more dynamic. But you wouldn't want either there.
If no prospect is ready for Vegas I'd say the better option would be to complete the 3rd line with Howden and try out prospects like Rondbjerg, Leschyshyn, etc. at 4C. Vegas' 4th line has historically been easy to play on.