BTWifi-X Not Found by Scan

My GL.iNet GL-AR300M16-Ext appears to be unable to find the following network when scanning for nearby WiFi:
[WPA-EAP-CCMP+TKIP][WPA2-EAP-CCMP+TKIP][ESS] BTWifi-X
The network has a good signal and is found without any problem by my PC and smartphones.

Is the network type not supported by the router and therefore not shown?

Configuring the network manually seems to result in a crash of the router.

EAP is ok. but Is it 2.4G?

Not BTWifi but similar - had exactly the same problem recently with a Mango and XfinityWiFI. The XfinityWiFI SSID was ONLY on 5G. Had another OpenWRT dual band router with me - scanning for wireless showed multiple XfinityWifi offerings, all on Channel 36 (US), none detected on the 2.4G “radio”.

Oh, of course, I didn’t think of it being on 5GHz only, that is most likely the issue. I will check when I am in an area where it is available next time and post back.