Nevermind, I think figured it out. It's still because of the inherited viceroyalty status of duchies, but there's a workaround. For some reason they make the ruler refuse to hand them out, but once I inherit/revoke the kingdom viceroyalty, I can go revoke all the duchies, give them back as normal titles, and then bury all the unhappy dukes under a viceroy king. Even if he inherits a duchy along with its counties, he now DOES give them back if he's over the demesne limit and/or has too many duchies malus. What a weird bug.
10asd
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