Mi Pad 5 (nabu) exposes strange behavior: when setting 5Ghz wifi to channel 60 or 64 the SSID shows up. Finding, connecting and using the wifi works fine. However when setting 5Ghz to auto-channel in router the channel is set to a channel in the 100+ range resulting in the Xiaomi device no longer showing the SSID.

This seems a common in Xiaomi devices as per:

Since running a custom rom can’t follow steps to report this to Xiaomi, but the reports are for MIUI and the issue is also encountered in ArrrowOS 13.1. https://xiaomiui.net/how-to-report-bugs-on-miui-7934/