Can't install RDM on Jump Host

Could you try re-downloading the installer? It looks like it might be bad/invalid signature.

The install log has:
Error 1330. A file that is required cannot be installed because the cabinet file C:\Users\pirol-ivufleet-admin.IVU\AppData\Roaming\Devolutions inc\Remote Desktop Manager\install\disk1.cab has an invalid digital signature. This may indicate that the cabinet file is corrupt. Error 266 was returned by WinVerifyTrust.
MSI (s) (2C:2C) [13:28:15:026]: Product: Remote Desktop Manager -- Error 1330. A file that is required cannot be installed because the cabinet file C:\Users\pirol-ivufleet-admin.IVU\AppData\Roaming\Devolutions inc\Remote Desktop Manager\install\disk1.cab has an invalid digital signature. This may indicate that the cabinet file is corrupt. Error 266 was returned by WinVerifyTrust.

Unfortunately that didn't help...

Action 10:52:06: InstallExecute.
Action start 10:52:06: InstallExecute.
Action 10:52:06: ProcessComponents. Updating component registration
Action 10:52:07: CreateFolders. Creating folders
Action 10:52:07: AI_ExtractFiles. Extracting files from archive
Action 10:52:08: InstallFiles. Copying new files
Error 1330. A file that is required cannot be installed because the cabinet file C:\Users\pirol-ivufleet-admin.IVU\AppData\Roaming\Devolutions inc\Remote Desktop Manager\install\disk1.cab has an invalid digital signature. This may indicate that the cabinet file is corrupt. Error 266 was returned by WinVerifyTrust.
MSI (s) (78:E4) [10:52:25:946]: Product: Remote Desktop Manager -- Error 1330. A file that is required cannot be installed because the cabinet file C:\Users\pirol-ivufleet-admin.IVU\AppData\Roaming\Devolutions inc\Remote Desktop Manager\install\disk1.cab has an invalid digital signature. This may indicate that the cabinet file is corrupt. Error 266 was returned by WinVerifyTrust.

Action ended 10:52:25: InstallExecute. Return value 3.

The .msi installer works fine, so it's only a problem with the .exe installer

Great to here that it works. No clue why the .exe wouldn't work.