Hello,
Yes I installed the new DC as an additional DC. Once I did that I did use the script provided to migrate the FSMO roles. I followed their two youtube videos on additional controller and transferring FSMO roles. I thought about using the rsync sysvol replication to get them over, but the issue now is, the old DC has been offline for so long, when I bring it up, workstations start authenticating against it and the credentials are all expired for everyone. So when I try things, I can only have the old one up for a few minutes before having to bring it back down. Also, I was looking and the domaindns and forestdns roles are still being held by the old controller, I can't get them to transfer either. Thought about seizing them but haven't tried. I did try resetting the SYSVOL permissions but that came back with an error too, so i restored to the snapshot from right before I did.