Sublease to a 2nd employee of a corporation?

[Brandi McBride]

Hi BP Community. A construction company reached out to me for a 3 month lease on my MTR condo for a super intendant working on a project in town. Their project was extended so they signed a 2 month extension addendum to total a 5 month rental. Three days before the 4th month ended (leaving one month and three days on the lease extension), they said thank you we don't need your condo any more and the super intendant is moving out in three days. That is also the point to which the lease was paid through (because I make rent due on the 1st of the month), so they still owed me for the 5th month's rent. Because it is a MTR, I only collect a 1/2 month security deposit. I reminded the office manager from the construction company she was still obligated to pay the 5th month's rent whether the occupant moved out or not, so she said, oh, well then I have another super intendant who will be moving on the same day as the current one leaves who is coming in to finish this project. She didn't ask, just told me that was their solution since they owed the last month's rent to me anyhow. The original lease says NO subleasing. (Yes, the tail is wagging the dog on this one.)

Since the lease is solely in the construction company's name (and not dually in the name of the occupant, which btw, feels like a mistake on my part), am I okay to just draw up an addendum stating I am approving a new occupant will be moving in with all other T&C of the lease to remain in place? Or should I draw up an entire new lease for the construction company to sign? These people have been extremely difficult to deal with, and they obviously have more resources legally and financially than I do, so I want to make sure my bases are covered. TIA.