Hay Beetle: Following up on your response here and I think you may have hit on the problem. That Chief's Special is a failry compact lightweight 45, isn't it. That might be the problem.
I have one of the original lightweight 45s, an older Colt Commander that has gone through a couple of facelifts. It has the beavertail grip safety, flat mainspring housing, Chip McCormack trigger group AND, it carries a 22 lb recoil spring package. All of this makes it manageable and an accurate shooter. But, when I go out to the range for practice with my full size Sprangerfield Gov't Model with the same accutrements I can go through twice the number of rounds that I feel comfortable in shooting from the Commander.
I'm not a big guy and I like my Commander but unde recoil she snaps, even with the heavy springs. I shoot only GI ball, which is what I carry. So, if your wife's Chief's Special in 45 is as light as my Commander, it can't be too much fun for her to shoot and recoil might be a problem for her. It sounds like she can handle your heavier pistols without a problem - they are most likely more comfortable for her to shoot or, because of the additional weight she might have to take a stronger grip but she can handle those without mishap or malfunction.
Your wife may like her Chief's Special because of the looks and the light weight but the recoil might be a bit too much for her. One suggestion for that pistol is a set of heavier recoil springs - you can get them from Wolfe. Also, think about the ammo she practices with - if it is the nasty hot stuff with a hollowpoint and extra muzzle velocity it can't be pleasant to shoot. The plain jane GI Ball may be a good choice, if she isn't using it already.
If the 45 caliber is just too much for her and the malfunctions continue, you might wish to consider another sidearm. My wife just loved her nickle plated Model 19, until she fired it. Then she just loved her AMT 380 Backup, until I saw how easy that could malfunction. After that she loved her Beretta 70S 380, until it recoiled too much. But she really loved her airweight Model 36 38 snubbie - lightweight, accurate, easy to shoot even with heavy bullets, and that became her sidearm of choice (until she learned to skip cans with her Beretta 21A).
Was that Chief's Special her idea or yours? Was it purchased because of its looks, weight or caliber, and who made the decision? If you can think of these questions and add in the recoil and weight factor of her current 45, you may come up with your own answers.
This is Mikey, again, and I hope this helps.