Hello, Thanks for sharing your experience and knowledge, I hope I can share as well. My life is full of joy and love with my family, Hubby, 5 yr old son, 5 yr old Blue Fronted Amazon Layla, and our new Boy Zack an African Gray. We bought Layla from a Flea Market at 6 months, I have taken it easy with her all these years. The only things she knows how to do are, I say perch and put my finger there and she goes there. I tell her to go home when its time to get back in her cage. and watch your feet when Im changing her food and water out, so she gets her feet out of the way. Zack was in an add, looking for a home after 17 yrs. He was only on seed diet. he sat in the same place in his cage didnt move except to go from food to water. He will now climb a little but still not shread or chew on anything. I have given leather, wood toys, ordered shreadable toys. Poor thing is terrified of anything new, that goes in his cage. But with time we will get it.

Well Thanks Again Angi
Welcome to the forum! You'll love it here
Your African gray sounds suspiciously similar to my galah. She was on a seed diet for at least 5 years, but most definitely more and had also been abused/neglected. She pretty much sat in one spot all day, unless she climbed to her playtop to scratch her head. She was extremely unhealthy, she had organ failure, calcium deficiency, was horribly underweight, she didn't play with toys at all, and slept all the time. It was almost as if she had nothing to live for.
Has your gray already been to a avian vet? Try to get him there as soon as you can if you haven't already and work on getting him on a pellet/fresh food diet. Never give up changing the diet, it took Rosie 6 months to stop eating seeds.
Rosie still doesn't play with her toys that much, other then foraging toys all her toys still look pretty brand new. I bought all sorts of toys to try to find the
one that she would just love. At first she liked card board and paper, and now that she's healthier(and on a great diet) she loves foraging toys and things she can preen.
All of the things I put on the bars are from planet treasure toys I dismantled. Don't be afraid to be creative, a toy doesn't have to be store bought or pretty, as long as it's safe and your gray likes it
That cardboard thing in the background came from a sparkling water box, it separated the the bottles so they didn't shatter. Since it has no glue I stuck a stainless steal chain and bell through it and she loved it.
Here's a example of how you can be creative with making new toys out of old toys to spark their interest.
Birds also usually love natural branches. Branches are a wild birds toy so it's no surprise. I give Rosie eucalyptus but it's only truly safe for Australian species.