If the backup generated through the installation procedure was lost there is no way of re-initiating it after the installation of FoE is completed on the primary server. You can use the Windows backup utility to backup the system manually and restore it on the secondary server yourself using the same utility and then resume the installation of FoE on the secondary server selecting the pre-cloned option. Another possible alternative would be to copy over the hidden nfsetup.dat and changelog.txt files from the C:\Program Files\SolarWinds\FoE\Support directory to the secondary server where the backup file resides and retry the installation on the secondary server.
Thanks. The location of the nfsetup.dat and changelog.txt files was what I needed. I'll give the installation on the secondary server another shot.