If not.......well, unfortunately, it's too late now and too bad ............you'll have to work this out with your Broker..
No one here can tell you what your Broker will or won't do in regard to commissons that may be due you.
it's good to get things in writing upfront.
I advise you to contact your State Realtor Association for some 'hands on' advise for your situation.
Very Best regards