I need some help on a topic of nominee adjustemnt on a property that I sold in 2022.

I sold my Second home in this year 2022 and my name was the only one on the deed. I wanted to distribute part of the gross proceeds to 4 siblings through the Nominee Adjustment process and I know that I have to fill out the form 1099-S for each of them and send the 1099-S form to IRS & my siblings.  There is NO paperwork that can prove my 4 siblings have an ownership interest in the property that I have sold.  3 out of 4 siblings wanted to use their children to represent them to file taxes for their shares of the gross proceeds.  I will pay tax on my part and they will pay tax on their parts.  Is this whole thing legal?  Will I be in trouble? Again my name is only on the deed and there is no paperwork that proves my 4 siblings co-own the property rightfully.