Hay is the most important part of a rabbits diet, so it’s great that she’s eating hay! It’s a shame the rescue didn’t give you some of the same pellets she was eating – can you perhaps call and find out the brand?
For a 2 month old rabbit they should be eating special young rabbit pellets, and Oxbow or Burgess are good brands. If you keep leaving her with a bowl of pellets, I think eventually she’ll start to eat them. You could try offering them to her by hand too. A young rabbit should have ‘unlimited’ pellets, but in practice, that often means giving them 1 or 2 half cups a day. If it interferes with hay eating then cut it down. Pellets do provide some nutrients so it’s important to give a young rabbit some, but you’re right, it’s not the most important part of the diet!
She is a bit young for veggies still. People vary on when you should introduce them, but personally, my vet said to start with small pieces from about 3 months. Other people think you should wait until 6 months, so it’s up to you, and depends how her stomach reacts to them. Some bunnies don’t react well until they’re older.