Leroy,
minors can be ticklish, especially when it comes to minor KEYS, not just CHORDS. Any given minor key has three different variants:
A minor natural: Am - Bdim ("G7 no root" for Carl Dixon

) - C - Dm - Em - F - G
A minor harmonic: Am - Bdim - C(aug) - Dm - E - F - G#dim (E7 no root)
A minor melodic: Am - B - C(aug) - D - E - F#dim (D7 no root)
Then there are, as has been stated before, quite a few rock/R&B/blues tunes that use major chords where one would expect minors - the intro to "Proud Mary", "Smoke On The Water" or "Sittin´On The Dock Of The Bay" - while the melodies use a minor blues scale.
But even classic country songs sometimes hold surprises. The middle part of "Rose Garden" (in the key of A) "... so smile for a while ..." goes: Bm - E - Em - F#7 - Bm - Dm - E. There are "passing modulations" into other keys in that progression that you just can´t anticipate if you just follow along by ear.
Take a look at the chord progession of "Girl From Ipanema" here on the forum. For me, at least, there would be NO WAY to anticipate those chord changes. I have to KNOW them, before I try to mess around with them.
The concept of "Just tell me the key, and I´ll manage" doesn´t always work out.
My humble advice would be: Make sure you know the chord progression of the songs beforehand. Contrary to popular belief, there ARE country songs that use more than three chords.
So buy the guitarist a drink - he might just tell you the chords. Buy him a bottle of Jack Daniel´s - and he might even jot them down on a paper napkin.

And if he empties that bottle before you´re on stage you can always point accusingly at HIM every time YOU grab the wrong bunch of strings. - That´s what I do ...
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Remington D 10 8/8, Session 400 LTD