I have always struggled getting bottle calves to eat any starter. As has been pointed out, they learn through imitation, so if you could put her with an animal that will eat she will likely pick it up fast. I just went through the same struggle with a twin. I had some success by switching her from the bottle to a bucket. She learned the bucket with only one lesson. I put my finger in her mouth and brought her down to the bucket and when she was sucking I removed my finger. Once she was using the bucket, I would let her empty the bucket and while she was still trying to get more milk, I put her grain in that same bucket. She would then go after it expecting it to still be her milk but instead would end up eating the grain. It did not work when the grain was in a different bucket. It had to be the one she had just emptied of milk. Prior to that I had been putting the starter in her mouth, so she knew what it was, but did not seem smart enough to figure out that she could eat it without my shoving it in there when she tried to suck on my hand.
Your calf is already 8 weeks, so old enough to be weaned if she were eating. I put good alfalfa hay out for mine, and she was eating that pretty good by six weeks. The starter was more of a struggle, partly because I had been feeding 3 times a day. I cut back on the times and the amount and that helped. They need to copy another cow or be a little hungry to learn.
A few days ago my last cow to calve ended up loosing her calf. It was coming head first but both feet back and I did not realize it in time. I was able to put my bottle calf on her, so now she will get to be a regular calf with a mother and friends to run with.
