I've driven past this place a few times. I can't imagine any self respecting punter going near it, it looks seedy, it's on a main road and there a bus stop 5 metres from the door, you couldn't be less discrete if you wore a sandwich board saying "I fuck hookers"
Not for me!!!
Why so worried about a bus stop outside? My fave place has one.
Personally I have no worries being seen entering but if you have reservations eg live local or are nervous, then just stand at the bus stop as if waiting for the bus and NOBODY will notice or think that unusual. Then when the coast is clear you should just have to turn around and walk into the place. This of course presumes you do not have to wait at the door to enter. My 'local' has an always-open front door and then you knock/ ring at an inner door
At exit you can probably peek out to see if the bus stop is clear of other folk waiting - or if you are real lucky the reception area will have a CCTV covering the outside door area. If you become a regular you may even find there is a rear exit they will allow you to use.