United boss Houston is now set to sideline the youngster after accusing his agent of demanding a salary which would have made him the third-highest earner at United despite playing just 272 minutes for the first team.
"Scott has rejected our offer and I'm very disappointed," said the manager. "He was offered the best deal this club has ever offered to a teenager, but he has decided he doesn't want it.
"When it comes down to a 19-year-old demanding to become the third-highest paid player at the club after two-and-a-half games, then I wouldn't pay him it even if I could afford it.
"That's what his agent asked for at first. He wanted wages in line with guys who have been playing at this level for years. I think he's being wrongly advised. That tells me where the priorities lie and I can't be bothered with people who are only motivated by money.
"He was made a very good offer but it's still not good enough for him. We won't give Scott any more money than we've offered because he's still to prove himself.
"He is a very talented player but can he do the work off the ball?
"He has had two good games - that's it.
"For me, he should be looking to play 50-100 games here and then look to move on to a bigger club.
"Look at the players who have accepted deals at Scotty's age - David Goodwillie, Johnny Russell, Keith Watson, Stuart Armstrong and Ryan Dow - and these guys have all become first-team players at this club."