A friend of mine suggested I post this as a new post instead of here
Just to update you guys on what has happened so far.
I emailed Patek about a month ago asking them this question. So far, I haven't received a reply, so I decided to use the watch while swimming in the pool.
As in the pictures below, I started the chrono underwater, waited a bit, and stopped it. I wore some goggles and looked at the watch underwater during this process. I did not notice any air bubbles escaping.
I then went to the deep end of the pool and went down about 1.5 meters, started the chrono and kicked off to do my laps. When I was done I made sure to stop the chrono while I was underwater.
click here to see the results.