I looked at the specs and the user guide for the Crane unit. It looks like a nice piece of gear, esp the extended antenna. As you said, it only operates on 2.4GHz, so my hypothesis about 5G was a red herring/rathole.
Static IP addresses are also a red herring. They would make no difference, and in any event, the Wyzecams can’t be configured with static IPs.
You didn’t indicate the name(s) of the various WiFi networks. You mentioned the main router in the basement, and another in your office. Are they both wireless? Do they both create WiFi networks? (with the same or different SSIDs?). And what is the name (SSID) of the hotspot in the barn?
Here’s one thing you could try. When you move from the house to the barn, it’s possible that your smartphone is still connected to the WiFi from the house (the technical term is ‘associated with’). Even though the WiFi signal from the Crane unit is stronger, the phone might retain its association with the house router. That’s quite possible, since the WiFi signal from the house is strong enough for the Crane’s external antenna to pick it up. WiFi clients are funny that way, and it’s difficult to predict how they will behave when faced with a multiplicity of WiFi signals. So something you could try is to turn off your phone’s WiFi (while in the house). Go to the barn, and stand close to the Crane repeater. Then turn on the phone’s WiFi. If its WiFi client is properly designed, it should then associate with the Crane radio (whose signal will be stronger than the one from the house). Then try going through the Add a Product routine with a Wyzecam in the barn, pressing the little button until the cam dings, etc.
Unfortunately, there’s a lot of black magic going on with WiFi, and with the Wyze implementation.
Hope this helps.
UPDATE - I just re-read one of your previous posts, where you said that your phone was on the barn’s network (from the Crane unit). So my theory about it still being connected to the house WiFi is all wet:-(. Even so, you could try following the procedure I suggested, though I am now dubious that it will make any difference.
From reading the Crane manual, it appears that it is a full-fledged router with its own DHCP and NAT, and is assigning IP addresses on the 192.168.8.0/24 subnet. That means that the Wyze cams will be operating in what’s known as a “double-NAT” environment. (all techno-babblespeak, I’m sure…). In the past, I have tested Wyzecams with double-NAT. They worked fine, but that was months ago, and was with the V2 cam (not the pan-cam). Some of the other folks on this forum might have some insights about double-NAT operation.