This is a very important Razz concept to understand. Razz is a pretty simple game, so the difference between geing a good player and an average player is getting full value for your hand when you are a statistical favorite.
In this case, based on your opponent's board you are certain that your four card draw is better than his. He is drawing to a 7-6, while you are drawing to a 7-5.
True, you could both double pair and the Queen low will win, but that won't happen often enough to worry about.
In the end, this hand is pretty elementary. Your hand will make the best hand almost 55% of the time. Razz is a game of small edges, so since we are absolutely certain that we are a favorite on fifth street, anything less than a raise would be a very big mistake.
