Someone else typed up the letter and the locations of the signers looks to be pre-ordained by the placement of their typed names on the page. The fact that DeSantis signed this 'investigation request' is good, of course. But the sequence of signers actually signing this document is not conclusive (nor is it even that relevant if you ask me). DeSantis could have signed this letter first or last or somewhere in between - we'd have to see video of people actually signing the paper to determine the actual sequence of people who signed it, IMO.