Apologies if I've chosen the wrong application for this. Of the small Linux team I'm on, none of us really understand KDE very well. It seems very difficult. But I'll go ahead and post my question.

We have a system that runs Rhel7.5 with KDE, but it runs gdm (this is one of the things that's very confusing). Anyway, the end-users of this system are military personnel. The account they use is auto-login with no password. They have very limited rights. An icon is provided to them, on the desktop, that when it's run, opens a terminal window that pings all devices within the system (other Linux systems, switches, etc.). We have to provide this for the users. It's an absolute requirement. However, the cyber folks are going nuts because when this ping test terminal window is open, you can hit CONTROL-ALT-T and a new terminal window tab will open. This is what we want to do away with. The ability for this particular user to be able to open a new tab in a terminal. The fix can't in any way interfere with the terminal window opening that runs the ping test.

We've checked in where the shortcuts are, custom etc., We don't see that anyone configured this manually. We can't seem to figure out how to fix this. I was just hoping someone else had an idea to point me in a new direction.

First off, what terminal app is being used, and what version? (I'm inclined to assume KDE's Konsole, in which case there should be a menu bar you can toggle with ctrl+shift+M. Under the Help menu you can select About Konsole to find out the version. Other terminal apps may provide a similar menu)

Assuming the terminal app is Konsole, it's keyboard shortcuts are configured (with toggling on the menu bar using ctrl+shift+M) through Settings -> Configure Shortcuts. However, I'm a little skeptical if it is Konsole because the default shortcut for New Tab in Konsole is Ctrl+Shift+T, not Ctrl+Alt+T.

For providing a terminal app for running a single terminal application, you might consider a more bare-bones terminal app such as Urxvt which doesn't even have a tabbing feature.