I am a new contractor taking over an on premises datacenter with a business process application that connects about 400 remote site which uses a critical business application on daily basis. The old contractor refused to give me access to the network and application so I decided to build a similar application and a new network to run simiulteneously with the old network. My app is 90 % complete and I have built a new datacenter with a fortigate gateway hosting my DNS and other servers. I just connected 5 remote sites when the old contractor intentionally crashed the old server and made away with the login detail. Now I have a situation in my hands to quickly deploy my app and extend my network to the remaining 400 site across the country. Kindly advise to migate lost of revenue through network down time . Thanks in advance

setting up an emergency respond team, and fastracking the completion of my app