|I need those balances to be highlighted in the file that contains the complete list of accounts|
I can't give you colors but will true or false work?
You could do something like:
Where A1 is your first account number, on your complete sheet, and column C on sheet number 2 is your recently used list.
Put it into an empty column and copy the formula down as many accounts numbers as you need.
True means a match.
You could also try something using =INDEX with =MATCH.
but again, no colors.