Steam Overlay Not Working

Having a really strange problem getting Steam to work and the overlay to appear… the weird thing is that this issue only happens on this specific project on this specific machine and only if launched as a Standalone Game from PIE.

It works fine if launched from Visual Studio with -game.
Steam overlay works for other projects on this machine even if they are launched as a Standalone Game from PIE.
Steam overlay even works for this specific project when launched as Standalone Game from PIE but only on on other machines.

Log simply says:
LogOnline: Display: STEAM: Loading Steam SDK 1.39
LogOnline: Warning: STEAM: Steam API disabled!
LogOnline: Display: STEAM: OnlineSubsystemSteam::Shutdown()

Thanks for any ideas…