I haven't done this before but based on logic you need to backup postgresql db then install other server from scratch with same config ( same url, secret key etc ) then after you initiliaze db you reset old db after it and since redis will be from scratch you will need to add other BBB-s in the pool again and I suppose acces to NFS will be already same as before if you don't move that too. Is Postgresql and redis at moment in same server where scale lite is or external ?
As I know so far postgresql have the data of recordings and redis only the servers list in the pool which you can add again same BBB servers.
Backup everything then try this process or more easier way perhaps clone the server over network with Clonezilla and give it a try.