If you saw their w2 or 1040, your claim would be more credible, since that's when most of us learn how much we actually made in the previous year.
If you look at one you have a pretty good way to extrapolate the expected TC for the year.
I'm trying to be nice to you by sharing information you can use in your future negotiations, but it seems you're just angry you are not making as much as my friend. Maybe next time I should just let you leave 100K+ on the table and go on with my life.
Also, doesn't Google famously have an internal spreadsheet where people share their salary anonymously? You can check that too if it still exists.