Upload & Sell: Off
I can understand a businesses desire for privacy of their property. However, if they have agreed to have a bride in this location (ie: they accepted money to perform a service), and that service generally involves the hiring of a photographer (bride hired you), then It's pretty silly to ask for images to not be shared.
You took the photo. You were granted access to their property. You can do whatever you want from the photos, granted you haven't signed anything that they have given you in order to gain access to this venue/area.
So, you don't have to be worried from a legal standpoint if you did decide to share the photos. I wouldn't sign or create ANY document to be signed.
No harm in sharing a few photos as long as the name of the venue, location, etc, is not disclosed in a public manner. Could you burn a bridge with the venue? Possibly, but it sounds like they dont want people there in the first place (which is weird).