Cannot access site but need to map domain

I am in a bit of a situation. I moved a sub site of a multisite site from one install to another multisite install. I am unable to get to the site in order to map a domain and was wondering if there is a way to manually do this? I do not see the option from within the network admin section of mapped domains which would be a nice feature but I understand could be dangerous. It is possible I am fighting some DNS issues too but I was hoping someone would have some ideas on how to tackle this?

Thanks for any ideas!