If you have a working backup of the SQL database from before the deletion you can restore this without making any changes to the application server. The restore will include any nodes that were monitored at the time, however you will lose the historical data between those two points in time. The 1 requirement is that the versions of the applications you currently have installed, were the same at the time you backed up the database, e,g If you had 10/.4 running when you backed up the database, and since upgraded to 11.5.2, you cannot restore the database.
Does that make sense?
totally makes sense. On it.