Thanks! That did the trick!!
Upped the Gateway RAM to 1300MB and then re-ran
sudo dpkg --configure -a
and then
sudo apt install --reinstall -o Dpkg::Options::="--force-confask,confnew,confmiss" apparmor-profile-anondist
… and then everything on the Gateway Just Started Working again 
Now I have another problem, sdwdate on the Workstation isn’t starting properly. But that appears totally unrelated; I’ll open a separate thread if I can’t get it sorted on my own.
And I’ve now subscribed to important-news tag, so hopefully I’ll see tips like this going forward.
I truly cannot thank you enough, but I did kick in a little