I would say it depends on what you feed her. Frozen/thawed? Prekilled? Live? Just a reminder you never leave a live mouse with your snake unsupervised. Most snakes won't eat around their shed time. So I wouldn't say it's not safe but if she's going to shed soon she probably won't eat.
Ive got a 55gallon glass tank, four Dixie cups of "soaked" sphagnum moss and two water dishes with one under the heat lamp and my humidity is about 50-60%. I easily bump it up to 65-70 with misting during shedding. Oh and tin foil on top with holes for air flow.
If you can, upload a pic of your set up please. It helps a lot to see
you can also make a humid hide for shedding days. Search in the search bar "humid hides".