There's no need to squeeze out the oil from the gel cap, just pop it into her beak and let her swallow it.
I'm glad she's doing better, but I'd keep up with the vitamin E and B-Complex daily for a couple of weeks.
Looks like Lash Egg a.k.a. Salpingitis.
If it's rotten smelling, then she's got an infection. If you have vet care, that would be good.
You can try giving an antibiotic to see if it helps, but often there's no cure for reproductive infections and disorders. Medication can help offer...