Not sure sure about my new chin (long story)

About a month ago we got a 3 1/2 year old girl chinchilla to make friends with our 1 year old girl chin. My boyfriend and I both work full time and even though we spend every chance we get with our baby Zoey we wanted her to have a friend so she wouldn't feel lonely during the day or night (our work schedules are always changing). Well I think its back firing on us. When I first found Maizy she sounded sweet and playful just like Zoey and I thought it would be a good fit. The person I got her from said she has never sprayed urine or bitten and loves to be held and petted by anyone. The day I got her the girl couldn't give her up fast enough. She never gave me a chance to ask any questions and told me shes moved around a lot. And I didn't like the way the cage she was kept in looked. It looked very sad with hardly any toys and there was no place for her to hide. Thankfully, I have a large double cage that can be either two cages or one very large cage. And I was appalled with the way she aggressively put her into my carrier. So naturally I'm glad I took her to give her a good home. But shes not getting along with Zoey at all! I feel so bad because Zoey will run up to her cage and make the contact call in a friendly way and Maizy instantly sprays her. After about a week or so of holding one another up to the cage with no violent behavior we introduced outside of the cage and when Zoey went up to Maizy, Maizy attacked her and it was chaos. So there has been no more out of cage play together. I know this could take a long process and they may never bond but I really want Maizy to work out with us. Maizy has also bitten and sprayed my boyfriend multiple times and she will barely let me hold her. But I can pet her. So my question is how can I help the bonding process for Maizy? I want her to feel safe and secure. Also, I have recently brought them both to a vet who cares for chins and they are both perfectly healthy.

Time is important for chinchillas who come from difficult situations. Zoey seems to be just frightened and not used to human contact. I'm glad you are spending time with her as often as possible, but I would start slow. Don't try holding her, start just petting her and letting her explore your hand; reward her with a small handful of oats or other healthy treats. Once she is used to you and your boyfriend, you can begin interacting with her outside her cage. You should also take the bonding between the two more slowly. Let them get used to being in seperate cage near each other, and once it seems that they are ignoring each other, begin a very slow introduction. Lifelong friendships cannot be forced! All zoey needs is lots of time and love! Don't give up on her!

If you have any more questions, feel free to reply!