Well the lawyer is wrong- in this case you are granting yourself a considerable benefit with a lease extension, without any consideration which as a director in this situation you cannot.
It can easily be overturned.
Do it at your own risk.
Based on the information posted, I offer my thoughts.Any action you then take is your liability. While commending individual effort, there is no substitute for a thorough review of documents and facts by paid for professional advisers. More ramblings atleaseholdpropertymanager.blogspot.com