Eggbound can cause death. If the egg got stuck and get crushed it will probably get infected.
Try the oliveoil and keep her warm. It helped one my girls, some month ago.
A prolapsed vent goes often together with eggbound.
I use a few drops oliveoil when pushing back the vent. This helps the egg flushing through.
Even if there is no eggbound, it keeps the vent more inside, while laying eggs.
Watch it often, as you may need pushing it back several times over...