Well, I do not have the answer to your question. I can tell you that I went through a similar situation. My son actually had been eating poorly since he turn 3 months old and since it had gotten increasingly worse. At some point in time, he was drinking like 3-4 oz for his meals, instead of his 7 oz. There were days that he was only drinking 24 oz - this when he was 5 months old. I had started solids also at 4 months, and even on the times that I witheld solids, he still would drink little. At some point in time, he was only taking 2 - 3 oz for his dreamfeed. I thought to eliminate it, but for a while I did not because I was using the dreamfeed to get him to intake more for the day since he was eating so poorly in the daytime.
Eventually, I saw no purpose in keeping the dreamfeed and I decided to eliminate it. When I did, he only lasted two days without the dreamfeed, because then he started to wake up at 2AM hungry. That is when I started back on the dreamfeed and I have not stopped it yet. Now he eats much better and is finishing all his bottles and all his solids and even drinks 7 oz of milk for his dreamfeed.
This does not answer your question, but at least you know that you are not alone. I guess if you decide to eliminate the dreamfeed, you can try it out. If it does not work out, you can always go back to dreamfeeding her.