Glad that you saw the vet. Did the X-rays show anything? Omeprazole can cause constipation, although it is used for reflux in humans. I’m not sure why they would use that, but I am not a vet. Maybe they thought crop contents were coming back up into the throat, causing the crackles? You might ask them, since her crop is full. Check it first thing in the morning, when it should be empty. Be sure to not use Dulcolax laxative, but only the stool softener. Dulcolax is only a brand name, and they see stool softeners and laxatives. The stool softener used for crop is doccusate sodium, generic Colace. There has been a lot of confusion over the Dulcolax name. Chilled coconut oil, cut into small peckable pieces is helpful.