Compare two columns and then produce the unique values - using a formula, not filtering?

Having trouble trying to compare the two columns of data and then produce the unique values in a separate location. I need to be able to do this for an electronic whiteboard for rostering purposes and see who is still available to be rostered.

I have defined names the for the ranges I am wanting to compare but having trouble with the next step, any help would be greatly appreciated.

P.S. I would also like this to happen dynamically i.e. when a name is rostered it would automatically update the available list. This is something required for both employees and then vehicles also.

I'm sorry but I can't follow the logic of what you're trying to do here.

If you have two lists - what's the difference between them. Is not one of the lists the master list with all the names? I'm not seeing the need to make this complicated with checking the difference between the two lists since they are both static values.

The idea is so that we can see at a quick glance what people and vehicles we have available for emergency works that may come in after hours so that we can allocate resources ASAP from referring to the list on the relevant day sheet.