macOS security (Gatekeeper) only trusts apps from the Mac App Store or those with a Developer ID signature by default, so unsigned apps are reported as "damaged".

Fix: open Terminal and run (replace /path/to/app with the actual path — you can drag the app into the Terminal window):

sudo xattr -r -d com.apple.quarantine /path/to/app

Press Enter, type your login password (input is hidden), and press Enter again.