Vedettes de Pont Neuf cruise to see lighting of Eiffel Tower

We want to take a 1 hr Vedettes de Pont Neuf cruise on July 31st at sunset to see the first lighting of the Eiffel Tower for the evening. The Eiffel Tower website says the lighting occurs at dusk. I looked up the time of sunset that day; one website said 9:33, another said 9:30. However, the Vedettes de Post Neuf website said sunset will occur at 10:08 on July 31st and that night cruises begin at 10:15 pm Does that mean the first lighting for the evening won't occur until after that? We want to buy skip-the-line tickets ahead of time. What time will sunset really be on July 31st? Is that the same as dusk? What time should we take a cruise? (The Eiffel Tower is about halfway on the cruise, and the Vedettes website says all of the tours at night will see the lighting.) Thank you. This is all to figure out which cruise to take! (It's really important to me--I'll have my husband, my grown son, his wife, and my 2 teenage grandchildren, so I'd love for us to see this. I'll save a few $ buying online and we can buy skip the line tickets. https://www.vedettesdupontneuf.com/cruises/ My friend, who went on a RS tour that included Paris, said they did this on the tour. I just can't figure out which cruise to take :)! Times are 8:45, 9:45, and 10:15 pm. I emailed the company (Vedettes de Pont Neuf), but did not hear back from them.