What is this black spot inside my belly button ? I am 7 weeks post op MMO. (photos)

It is not clear from the photos what the nature is of the dark spot in your belly button.  It could be a scab or small wound.  I recommend following up with your surgeon for further clarification.

It is difficult to tell with this picture alone, you would need an in person follow up with your PS for further examination.

Dear jbee8989,it is hard to tell for sure without an examination. I would suggest you to consult your plastic surgeon. Only after a thorough examination you will get more information and recommendations.
Daniel Barrett, MD, MHA, MS 
Certified, American Board of Plastic Surgery  
Member, Am. Society of Plastic Surgery

It is very difficult to say for sure what the dark spot is based on a picture. The most common things that occur at the belly button during the healing process is a small wound or delayed healing. This usually does fine with some local wound care. It could be nothing more than a small scab and needs nothing. I recommend seeing your surgeon and he can help navigate this with you.

The pictures are not clear but it does not appear that your belly button is dead but maybe a small portion of it is dead (necrotic), if this is the case it should heal with just a little wound care over the next few weeks.   Follow up with your plastic surgeon for advice.

Difficult to tell for the photos and although it is usual to have scabs etc it best to gain reassurance from your PS.