Create a sheet with the originalowner (your holding account in your case), newowner, folderid of the folder you want to transfer and if you want the current owner to retain access to the folder a role column retainrole which can be none editor etc you will probably want none. I called my sheet ChangeFolderOwner catchy I know.
Then run you will need to run a gam batch command
Create a file called newfolderowner.bat which contains the following code
gam csv gsheet sheetowner@org name ChangeFolderOwner Sheet1 gam user ~originalowner add drivefileacl ~folderid user ~newowner role editor
commit-batch
gam csv gsheet sheetowner@org name ChangeFolderOwner Sheet1 gam user ~newowner claim ownership ~folderid retainrole ~retainrole
commit-batch
gam csv gsheet sheetowner@org name ChangeFolderOwner Sheet1 gam user ~newowner update drivefile id ~folderid addparent root
The first command adds the new owner to the folder as you can't give ownership of a folder to a user without them having some access to it
The second command does the change of ownership and the third command puts it into the users root directory.
To run this command use
gam batch newfolderowner.bat
commit-batch is used to ensure all steps complete before the next starts.
There are probably better ways of doing this. I haven't tried it with lots of files and it isn't fast but it works for my use case of giving ownership of a few files and a directory to a user and removing me from them. I'd be interested to hear how it works for larger folders, but do run a few tests before you use it in anger. I'd be tempted to create a filetree of any folder I was testing on so I had a record of all the files just incase.
HTH