The airline wants to disable the logo lights indefinitely as a maintenance saving. However the MMEL effectively stops them from leaving the system inoperative for more than 120 days.
Then have them correctly removed by either an STC, approved EO, or field approval. As stated earlier, if it is installed, it must work or the aircraft does not meet the design data. So in the US, it is one of the above methods to change the design data. I know that a field approval is not available out side the US, but an approved Engineering Order, or and STC would work I believe. The removal could be as simple as removing the CB's and switches, or something along those lines. Or the operator could have their MEL changed (by the certification people) to delete them.