about your historical question...
No, IWC had no connection with Cousteau himself. But don't get too much out of the Blancpain-Cousteau connection.
Blancpain is a different company, with different watches today, and Cousteau also dived with other brands. Also, if you Google "Cousteau watches" you see that one of Cousteau's sons has licensed the name to some very inexpensive (under $200) dive watches, which probably have more right to the name. Of course, IWC has a right to use the name given its agreement with Francine Cousteau (his widow) and the Cousteau Society.
On the history of diving watches, over 10 years ago I wrote a history of them. It was taken down due to a dispute regarding republication rights. However, several other websites then picked the article up and without my consent republished it! One such pirated link is below, although the article was edited to delete images. I guess they respected some copyrights!
click here