My theory... I think that the first time Mrs. Burnham used the suit was when the Klingons attacked. She probably jumped into the suit to escape getting killed, and didn't have much say in where the suit went the first time. It was just by happenstance she ended up in 2053 Richmond, Indiana during WWIII. This makes the most sense for the fact that it's the only Red Angel appearance that doesn't really tie into any of the other appearances. It was a happy accident for those folks about to be A-bombed into oblivion.