The risk of raising suspicion is quite low IMO.
When hotel rooms are used for punting by far the 3 most common scenarios are:
1) The WG has the room booked (often for several days, she'll be taking multiple in calls)
2) The punter had the room booked anyway (so is staying at least overnight)
3) The punter uses one of the "day use" options where he finds a room where he only pays for an hour (not sure if they have that in Leeds...)
I'd think it would be rare that a punter would book for a day & then check out after an hour, as that's not good value.
By chance though I did something similar myself a couple of months back - checked out of a holiday inn in East London only 3 hours after arrival. I just told them the room was fine but there had been an emergency change of plans so had to leave early. They confirmed a few extra details, then gave me a £25 refund which I didn't even ask for. I detected no sign they had any suspicion.
And if they did, it would probably be that the room was used for an affair rather than punting.
In Leeds, if you don't mind paying a few quid more, the Crown Plaza hotel is a nice big anonymous building. (Been over 10 years since I stayed there though, so not sure if they have key cards blocking access to the lifts now.)