That sounds like the correct entrance. It isn't very inviting and you can easily miss it, especially when it's dark.
Google's placemark is on the wrong side of the street. As you walk down Dona Carmen Cathouse is on the right hand side, behind Stardust.
I have personally verified every placemark I added to my map, and I'm fairly confident every one is in the correct place.
Ah, sorry about that - the street view just had me turned around. You're quite correct - it's Google's marker that is in the wrong place.
And looking down that side street from Kalayaan, there's actually a much larger, vertically-oriented Cathouse sign facing that street.