FYI, I've been corresponding with Gumption over the past couple of days and his Nature Tours on Necker Island have been resumed - at least through October. As presumed, it seems that some guests may have gotten carried away with their use of social media. Therefore, tour guests will now be required to sign a social media policy form. I just hope that all guests start respecting the opportunity so I can experience it in January!
Here is the updated page of his website.
Gumptions Nature Tours on Necker Island