Apologies if there's a similar thread, but search returns very old threads.

I'll be in Paris by end of April, and plan to visit the tower and go to the summit. But tickets are already sold out in the official eiffel tower website.

If I buy from 3rd party sites like viator, is it really skip-the-line?

If I buy tickets with dining at 58 Tour Eiffel, which gives me skip-the-line access to the 1st floor, how can I access the 2nd floor and the summit? Should I buy a separate ticket for the summit?