Aw lucky you! Cuddles all around lol.
It shouldn’t hurt them to try a bit of the greens. that’s not unusual. Are they trying hay also?
They do go for these foods now. They might be fully on solids by about 4-5 weeks. Some may still sneak in a feed from mum. I think I saw Potamus try get a feed from her mum when she was about 10weeks old. Lol !
Even after they’ve weaned themselves off milk, it’s important they still have interaction with the adults so they can built up good gut flora. You’ll start to see them producing their own caecotrophs also.
With the sipper bottle, I think you’ll find they’re curious enough to try it out! They might bump into the tip a few times, get droplets on their fur, then go back to investigate. Just make certain you position the bottle low enough for them or put a little box in front that they can use as a platform.
If you find they don’t naturally take to the bottle, smear a bit of banana on the tip. At the moment, they’re probably getting enough fluids from mum.