Hi there peyperj,
That sounds like a very good and varied diet you are giving your grey. What I tend to do if Beau's poos are a little too watery, is ease off the fruit & veg a little the next day and offer the egg, this should help. I give Beau approx. half a dish of fruit or veg daily, if he particularly likes what I give him it is usually gone by lunch time but I don't offer more until the next morning as he has his pellets and mixed parrot food if he is hungry. If you offer both pellets and fruit at the same time this might also help as he would probably eat them both taking in a little less fruit.
Have you tried palm nuts? Beau loves these and grey's eat them in the wild as they are readily available. I give these about 3 times a week, one lagge one or two small. If you offer a varied diet, go easy on the vits.