My answer is no, there is no established, concise term for the situation you describe.
If you said my group went on a weekend retreat at ABC Country Lodge, you are more than likely going to be asked to clarify the meaning of retreat. Like, a retreat, huh? What kind of retreat or what was the retreat about or what was the purpose of the retreat? This is because retreat has the meaning of a group of people, often a specific group, attending a specially organized weekend ordered around a specific topic in order to do or study or attend talks and/or meditate on that topic. Such a retreat does not even need to be held in the countryside, it could be held at a meeting center downtown.
Oddly, the phrase "retreat weekend" does not seem to carry with it all the garbage, er connotations, that weekend retreat does.
And a getaway does not necessarily mean a getaway into the countryside. There are people who relax better in the city, or at least in a crowded urban amusement park. And plenty of weekend getaways are made to Las Vegas.
I stand by my comment that was meant to imply that every native speaker in the USA would know (in general if not in detail, as in did you play horseshoes, Frisbee golf, bicycle, fish, etc.) what you meant if you said, my family or group spent a weekend in the countryside.
However, as that is not concise, you could just 'invent' a term for your minutes and say a countryside weekend. Or use the original foreign language phrase. It's your minutes, after all, and foreign terms are adopted when native terns aren't ready-enough synonyms. But the more I look at countryside weekend the more I like it. And 'retreat weekend' is also good.