New Launcher lost me my local server alias

You tied my mojang account to my microsoft account today. No choice or warning. So I lost my Dad alias for my local server. ie it ignores 

"displayName" : "Dad"

in

AppData\Roaming\.minecraft\launcher_profiles.json

All I need is to get in once and put all Dad's juicy stuff in a chest before he is binned. How can I get in again?