How do I restore a case-sensitive, journaled Time Machine backup to a case-insensitive, journaled filesystem?
The correct answer (after several days of experimentation) was to remove all ambiguously named files that would have a conflict. Then using another admin user, restore the original user using migration assistant. If you don't remove ambiguously named files, migration assistant will move what it can and then fail at some point giving no indication that it actually failed. You'll be without data and you won't know what.