Having one party to run the system wouldn’t need a block chain, just transparency. Make the data public, available to everyone, with daily hashes of the data of the day combined with the hash from the previous day. Sign that hash+date to prove it has been computed by this central party alone. If the hash cannot be recomputed then there is proof the data has been tempered with. All other parties need to do is to download and store these daily hashes in case of a conflict.

But all of that would be vastly simpler with a central trusted third party.