Conditional Formating to highlight cell (text word) if not included in a table of words

Hi,

Is there a way to set conditional formatting to highlight cells if the word/name is not included in a list.

I have a complex table that gets filled out by a lot of different people in bulk via copy and past.
The data is set up via data validation dropdown list, however due to volume this is not used. (e.g. some people will need to complete 12 columns x 500 rows each day).

The people inputting information are responsible for ensuring the data matches set criteria, otherwise when I consolidate and try to upload it spits out errors.
Errors can result from as little as an added space, misspelling, or something completely invalid.

They do try to review, however again due to volume it is hard to pick out a minor error.
My idea is if it highlights the cell due to it not being in the list, then they can filter for colour and correct.

An added complexity is our IT security systems don't allow VBA's on our laptops.

Thanks!