No. Stop draining the crop and just massage it gently. From the top to the bottom. It helps pass some of that gunk through.
They can easily aspirate if you try to empty the crop. I did it the first day and then didn't bother any more. No fruits or anything with even natural sugar. No bread...
It took about a week for my RIR to clear up.
Nothing with sugar. Cooked rice would be okay, but eggs would be better.
Are you using plain yoghurt with probiotics?