Do you know what the query is that would return the same info (Object Name, Object Type, Lock Type, Lock Owner, Lock Mode and Date Acquired) outside of ArcCatalog (e.g. from SqlPlus)?
The reason I ask is that there is a bug (BUG-000083139) that causes the dialog box to respond very slowly for geodatabases with a considerable number of versions (ours is over 30k), so if it's possible to do this from the command line it would make it a little easier to work with.
And in the situation I describe (our DEFAULT version locked), would the Lock Mode in the Geodatabase Administrator show as 'Exclusive' to pinpoint the locking session? Oftentimes the Geodatabase Administrator will show multiple 'Shared' locks, which are not a problem.