Orbi Outdoor Satellite Used to Work, Now Does Not

Greetings friends - any helpful ideas would be most welcome.  Details below, but in short, I'm trying to get an Outdoor Satellite to reliably work.

The setup in the house is cable modem to the Orbi router (RBR50).  This is on the ground floor of a 1905 home, with some drywall but plenty of plaster.  On the second floor of the house is a satellite (RBW30), and on the third floor of the house is another satellite (RBS50).  The basic footprint of the house is about 30' wide by 35' deep.  So far, so good.  This all works just fine.  I get max speeds just about anywhere inside the house. 

Last fall I added an Orbi Outdoor satellite (RBS50Y).  I hung it on the back wall of a garage, such that it was roughly 150' from the router.  Without any drama (that I remember), I got that thing working and it was fantastic.  Max speeds all the way out to the garage, and pretty much everywhere else in between.  But over the winter, the Outdoor unit began cycling through the different colors - white, blue, amber, and magenta.  I started losing connection to the smart switches out there.  I fiddled with the satellite, reset it, re-synced it a million times, but I could not get anywhere with it.  I never got it to do anything but cycle through the lights.  So, defeated, I returned it to Costco.  My best guess, which was only that, was the record low temps of between -20F and -30F (well below the rated temp for the device) had ruined it. 

But this left me with precious little signal in the garage, leaving my smart switches useless and causing other (admittedly first world)  inconveniences.  So, I just took another stab at it with a new version of the same Outdoor Satellite.  Long story short, I've got exactly the same problem now.  After successfully syncing it in the same room as the router, I can't get it to work for very long anywhere else on the property.  That includes a couple rooms away from the router, on the deck attached to the house, or in the same spots as the other indoor satellites listed above (which work fine!).  And it certainly does not work in the original location, on the back wall of the garage, where I really want it.  No matter where it is, it shines blue, then the light shuts off for a while, then magenta comes back, and so on.  Sometimes I see amber, but not often.  I've reset it another million times, and no joy. 

So, please let me know any suggestions.  The one thing I haven't done is reset the entire system.  I don't have any reason to believe that would help, and therefore I don't want to do it.  I also don't want to because I think that would mean reconnecting myriad IoT devices.  I also don't see why I should have to. 

Some questions:

1. Why would the original Outdoor Satellite quit working suddenly and definitively, after months of solid performance?
2. Why might it be that the new Outdoor Satellite won't work even in locations where an existing indoor satellite does? 
3. If, despite #1, the distance to the garage is just too far to reasonably expect it to work, what other solutions, Orbi, Netgear, or otherwise, can you think of to flood that garage with WiFi. 

I'm out of ideas, and ready to return the second Outdoor Satellite to Costco.  Thank you in advance for any thoughts.