Greetings
tpotts1984,
At three years of age, she may be having reproductive changes that are making it hard for her to expel eggs.
If you don't think it is respiratory, or heat related, it may be reproductive.
The epsom soak is good but you need to administer a calcium supplement. A half Tums tablet is enough. The calcium will help her muscles contract and hopefully she can expel the "egg". However, I suspect she has a collapsed soft shell scrunched up in her oviduct and not an egg. When you soaked her did you feel between her legs and vent? You may have noticed the feathers were wet or dried crunchy. She may have expelled the white and yolk already.
When the hen is in distress, and I suspect trouble expelling an egg or soft shell, I like to crush the half Tums tablet into powder, then mix in enough water to make a suspension. Then, I give it to the hen with an oral syringe. The calcium will move into the gut faster if it is liquid. Give her a couple hours to get things going.
If she is eating and drinking you have time to determine what the problem is. The antibiotic may help prevent infection if any internal damage happened, also administer a vitamin with iron, as a hen can become anemic from this.
God Bless
