Resident Blind cat not happy with new blind cat

[somersetfit]

Hi
I do adoptions and we rescued a blind cat that was left behind when her owner moved. How she made it outside for 3 weeks during last years heat wave is beyond me.
I found her a home last month they have a cat that is her age 10ish and blind.
They had them separated with a gate between them so they can smell each other. I told her she should be able to let them mingle while she is around to supervisor, it's been like 3 weeks since she's been there. She rubbed a towel also to mix the scents but seems when Tansy the cat she adopted comes near the resident cat Angel ; Angel hisses and wants no part of her.
I see someone put to reward with treats when they are together. Being she is blind also I am sure she is scared. Is there any other thing that can be done so that Tansy does stay in her new home. I will take back our rescue cat if it doesn't work but really a great home and hoping it does.
Any other ideas for her to try in helping them get along. I worried this will not work and maybe her cat wants to be the only cat. There are two small dogs in the house and Angel gets along with them with no problem so I would think she would be fine with another cat in time as the owners thought.
Thank you
Carla

[critters]

I would say that I don't think things are going too terribly for only 3 weeks. Tansy will probably hook up with the dogs to be her friends, and that's fine. I expect they'll work it all out eventually, and Angel probably will be essentially an only child.