Shoulder press is overhead and 300 lbs would be nigh impossible. Bench press however, where she pushes up while lying on her back, isn’t impossible but 300 lbs is a LOT for an average female. The old standard was that you should be able to bench 1.5 times your weight as a measure of health. That’s likely twice her weight. Not an impossible feat and damned impressive.
That's a good-sized multiple for bench, which is all upper-body. I've heard 1.5x defined as a high-fitness "goal."
I did that at 47 and set a state record (men's 48-and-under, 147-lb. class).
I should point out there was a snowstorm on the day of the meet, so it was just me against the record book and the judges.
I saw on her Truth Social she was deadlifting about a plate (135lbs). She’s obviously strong and in shape but no way is she benching 300