I'm currently working on a redesign of a very large/complex website with tens of thousands of pages and hundreds of contributors. The new design requires a significant departure from the current site structure and legacy content must be migrated and formatted accordingly. I've done my best to familiarize myself with their content and their processes and I've put together a proposed sitemap that I think is a good first step.
However, the client kind of rubber stamped the sitemap and wants to move on with wireframing and design. I am concerned they haven't fully considered all of the complexities and possible use cases my round 1 sitemap might not account for.
Are there any suggestions on how to use a sitemap to help the client dig into the nitty-gritty details of their own needs and flush out edge cases that I am not yet aware of?