There are assumptions being made over what was/wasn't said and talked about in the FO and between FO and player.
Unless facts are known, isn't it easier to create a favorable scenario rather than create a negative one?
I'll make one up quick.
They promoted Jones for a few days knowing they would DFA him as soon as a replacement elsewhere became available or when Hamilton was back, keeping Leonard as depth and giving Jones an option to be claimed to get an opportunity elsewhere. Then when they acquired Shewmake -> Leonard asked for his release to see if there was another opportunity available to him. If so, best of luck and thank you. If not, resign a MiLB deal and come back in a week.
We did this same thing already this year with both Strzelecki and Waguespack.
Of course you could be right and the Brewers fumbled him away. But I can only assume if he has trade value he would have been dealt already... So isn't the above scenario both ethical in trying to preserve depth for the team but also doing right by the players to give them him a chance elsewhere if it wasn't to be here?