I have three boys (Canary, Star finch and Zebrafinch) so artifical nests are fine with them. They pull them apart and carry everything around. Try a small bundle of feathersm fresh grass or dried grass...they love picking them up, pulling them apart, and nibbling on them. My finches have mirrors also. I also rotate what toys I have, and also the set up of the cage...it keeps them busy and thinking
Good luck with yours
Zebrafincher