The thesis defense is due in six days. If it is 20 days late, will it be accepted?
You should contact your thesis supervisor as soon as possible to see what his specific opinion is. Your defense is on the 25th. It shouldn't be too late to hand in your paper these days. I replied on 18, and another student handed in the paper at our defense site. So don't worry too much. It's not too late to contact your tutor as soon as possible.
Good luck! !