With a toy like that, I would just sit back and physically do nothing other than roll it once or twice (which you already did). I'd tell her to "get it" or indicate the toy somehow, then ignore her. Praise when she approaches the toy, then when she touches the toy, etc. She'll probably bump it by accident the first time or two before she makes the connection.
If the Kibble doesn't fall out easily, you might try a smaller, higher value food first to increase her desire to get it, and make it more likely that pushing the toy results in food falling out.
Good luck
If the Kibble doesn't fall out easily, you might try a smaller, higher value food first to increase her desire to get it, and make it more likely that pushing the toy results in food falling out.
Good luck