Smith-Rowe is on something in the 100-120k per week range by most reports but a club like Fulham can pay that no problem.
ESR is an exciting gamble for a side like Fulham. His injury record is poor but he is very talented and still young and there is a scenario where you he stays healthy, has a breakout year, and then Fulham have an English international star on their hands that they can ride for a few seasons and eventually sell for a significant profit. ESR also works within the context of a team like Fulham that wants to be able to play with the ball against the weaker sides and needs creative players to feed a classic CF like Muniz - he'll play LW where Willian played sometimes, CAM instead of Pereira sometimes. In contrast, its not really clear how McTominay works within the Fulham side. He's not enough of a true DM to be a replacement for Palhinha, he's not the type of attacking midfielder they seem to prefer, they already have both Harrison and Iwobi as box-to-box players.
McTominay is a hard player to fit into a side, for the same reasons that United has found. Its easy to say that some midtable side should want that kind of box crashing midfielder but most of these teams have managers with different tactical ideas. There aren't many Moyes types managing in the PL anymore.