OK, so your library stack on your system is good, there is some runtime, somewhere that is overriding and loading wrong libraries when your gnome-terminal is invoked.
As for how to check whether or not flatpak is involved, I don’t know what packages you install, but you would know how you installed Lutris on your Linux Mint for starters. I presume if installed using apt, it would install lutris normally.
I’m on a vastly different system than you are, I haven’t seen a *buntu environment in probably 2 years, nor Linux Mint itself, and I can’t guess.
I should think disabling the lutris runtime would take care of that, but if running the install script for the Epic Games Launcher, that might be chicken before egg if changing it in the existing prefix if it’s already been generated from a previous attempt. The lutris runtime can also be disabled in global options.
I can think of a workaround though, use a different terminal. In the settings of your desktop environment, change your default terminal application to xterm or something.
Look up how to do that for your desktop environment and distro. (e.g. Ubuntu/Gnome) if it’s not readily apparent. (Gnome doesn’t like people changing things and often doesn’t provide such settings in the UI… might have to set an alternative, or even create a symlink). I’m finding different answers for that, which is why I’m saying to look up specific info of appropriate age.