Understood. This is not something Wild Apricot supports now :-(
We do have plans for many enhancements for multi-chapter organizations but these are about a year out.
For now the only work around I can think of is to open separate WA accounts for each chapter - and then you can also have a WA account for the umbrella organizations where you can e.g. have a page with a list and links to all chapter events.
Dmitry Buterin, Chief Apricot