This ^^^ exactly is all you can do. Most kids do not know what their parents’ assets are. You can have a good idea, or not. The assets could be in qualified plans, have margins loans against them, just as examples. Unless you’ve been given access to all the info and explanation , you really do not know.
As @kelsmom states, it’s up to your parents to report and sign off on the info. Make sure you report your part of the FAFSA correctly.
It’s a fact of this whole process that dependent students are very much dependent on the parents they have. If parents refuse to fill out the FAFSA, and many do, or do not fill it out correctly , it’s a problem Always a problem., and without an answer because your parents cannot be forever to fill out FaFSA and the consequences of getting caught filing incorrect info is to you.