Bret was and to an extent still is a master of hiding his political abilities. He was the middle son who never wanted to be a wrestler, yet ends up the most successful over the "better workers" like Bruce and Owen... yet he was always the "reasonable one" on the surface, where Bruce was "outspoken" and Owen "the joker".
I can well believe Nash pushing for his finish, but by then it was also known Nash was leaving... Why should Bret then help make him look any stronger for the competition?
When it came to Montreal, Bret was selfish - he was selfish to an extent not dropping the title to Davey at IYH 5 in their rematch he had to get "his win" back, a criticism levelled at Hogan in the past.
But Bret was in many ways a good kind of selfish, he looked at it from a fans perspective more than Shawn, Nash or Hogan did... or rather HIS fans perspective, so he was if anything a little short-sighted rather than out and out selfish. The only time he balked was to Shawn on his way out... how many times did Nash, Hogan or Shawn use the "that doesn't work for me brother" or a variation of it?