Hello there:
I would not let him use a ball, chins can overheat in them.
Are you sure it is a male? Males generally do not pee on people, females are the ones who spray. You should have your chin sexed by a knowledgable vet or breeder in your area.
It seems as if you need to start bonding all over again.
Sit near the cage with door opened or not, let the chin come over to you and check you out. During this time do not try to grab it. After about a week of this, you can start trying to pet the chin. After a month I would say you could start attempting to hold him/her again. While letting chin check you out, you could offer him/her some treats, such as half a raisen once per day, shredded wheat (non sweetened), or rose petals/hips.
If you need any supplies checkout tjschinchillasupplies.com , I have bought many nice things from Jean.
Try not to scare it no matter what, make sure when you go to pick it up, it knows you are there, and you are not sneaking up on it.
This is all about building trust.
I hope this helps.