It works now that I resoldered the pin on the BAT54S diode (pointed to with pencil), so the backup battery actually connects now to the DS2432 counter. 
But now I just discovered that the WiFi range of the WEMOS D1 Mini does not work so well where I wanted to put my weather station: a shed in my back yard. I’m getting RSSI values of -85 dBm and lower. I’m considering moving the router to see if that helps. Right now, the signal has to go through basically an inside wall and siding of the outside wall. Also, I’m looking at an external antenna for the D1 Mini or buying a D1 Mini Pro with an antenna since according to some users doing that really helped. At least I’m getting closer to the end of this multi-year (jeez) project. It was pretty much shelved (again) during the summer because of other (non-electronic) stuff to do. 🙁