MagniFi MAX: Subwoofer won't sync, serial number doesn't match with soundbar

For hours, I tried to sync soundbar and subwoofer and could not get them to sync.

Got the beep when I pressed "SYNC" on the sound bar and the two tiny LEDs started to blink, for satelite surround speakers and for the sub.

The subwoofer was already blinking green, which I think means it's trying to sync, but I pushed the SYNC button anyway. I tried pushing it briefly, 5 sec, 7 sec, 10 sec, 30 sec, 60 sec. Never a beep, as the manual said there would be. Usually after about 5 sec, the blinking rate increased of the soundbar LED, which looked promising. But after two minutes, no sync and the sound bar would issue a 'blurp' sound. The two tiny LEDs there were no longer blinking, as it evidently timed out.

A got the sound bar connected to house WIFI through Chromecast, saw what appeared to be an update occur (disconnect, reboot, LEDs shining together). So I tried it all again, but nada. Well over two hours wasted so far.

I took a photo of the sticker under the subwoofer and wrote down the subwoofer code/serial number.

I took a photo of the two stickers under the sound bar. One has to do with ethernet adapter and wifi adapter.

The other is the model/serial number, which is *almost* identical to the the one listed on the Subwoofer. It's like this:

AM82181120A9977 -- sound bar
AM82171120A9977 -- subwoofer

Does this mean I was given a mismatched set that can never pair? IF so, are there DIP switches in the subwoofer that I can change to get them to match again? What do people do who try to replace e.g. just the subwoofer (e.g. the way one can pair a garage door opener to a remote)?

It doesn't appear that there's any way to run analog or digital out from the sound bar to any generic subwoofer so it thnk the only way to pair a subwoofer to this soundbar is via the black box pairing. SO if that doesn't work, nada. (Truly hard to believe there isn't at least a failsafe RCA out....).

Or maybe this is what the serial numbers should say, and it's just faulty? I did connect my bluetooth phone to the sound bar and play music from my phone through the soundbar, if that helps shed any light.

Any ideas? I'd hate to send this thing back, it's quite heavy and I'm sure the cost would be greater than the value of the subwoofer. But I would like to get the subwoofer to work.