Why raise? Only two limpers so the field is nicely thinned out and I can see a free flop, would have definitely raised if there were 3+ limpers.

Who is four betting with 99s? Best case scenario you're in a race. The object of good poker is to get it all in ahead everytime, and not just 52:48 but 70:30 ahead.

Pocket nines is a good hand but it’s still a speculative hand. A raise might win a small pot however limping will win the really big pots that you need to win tournaments. Flop a set and take down the whole stack of Mr top pair top kicker.