I think it's because it's on TV rather than Leeds doing it.

I’d hope we’d go with Russell on the wing instead of Walmsley to help with yardage due to the strong Leeds defence…

Rourke
Russell
Hall
Pratt
Johnstone 
Jowitt 
Lino
McMeekan 
Hood
Faatili
Croft
Griffin 
Pitts


Subs
Vagana
Cozza
Nikotemo
Smith

On the other hand Walmsley I reckon is the better finisher.  

Can not understand why Walmsley as not played all season, one of the best finishes we have had down at Wakefield in a long time .The main problem he as had ,like T J is a lot of the passes he as had ,have been shocking ( Not having a go at Hall of Pratt luv them both ) but both are still young and work in progress .and overall do not think Walmsley as made no more mistakes than any other player in the team I myself .will be sad to see him go,If we do bring a new winger in to take us to the next lvl would have been a good back up

It's not a matter of mistakes.
Early on he has not shown that he can get us off the line like Russell can but he seems to have fixed up that part of his game so deserves his place.

Well let's hope the game is closer than tonight's academy match between the two sides.