Usually the logout after a game is the result from a server being restarted during your game (usually for performance reasons, when it bogs down too much).
The best way to get a past results is joining the dominion discord at
https://discord.gg/MGAqrH9There is a bot called "Dombot" (a "user" that is actually a program that has access to the database of played games) that can answer this (and many more) questions!
You have to send the bot a direct message, and type a command:
!prior Ingix
would list my (Ingix') last 5 rated games. If you substitute your username, it will list your last 5 rated games. If you are after unrated games, then you need to know who you played against.
!match Ingix, DonaldX
would list the last set of consecutive games of Ingix vs. DonaldX (not his real account name). This command goes only back a few days, but should be enough for the "I just got logged out" scenario.
!help
lists all the available commands (many more).
As to how to prevent this, there is nothing you can do. Over the holidays more people than usual play, so the servers get loaded more heavily. Server load should go down now when people generally go back to work and have less free time.