Trying to get my picky conure to start eating roudy bush pellets

I have two conures a pineapple green cheek named kiwi and a brown thoat named Charlie. My babies are currently eating zupreem pellets but I'm trying to switch them to roudy bush pellets so I got them some free samples to see if they would luke them. My kiwi has never been a picky eater and is already eating the roudy bush pellets and likes them. But Charlie has always been picky and its been hard to get him to try new things and hes not really into trying the roudy bush pellets yet. When we first got Charlie it took us the longest time to get him to try fresh fruits and nuts and to switch from seeds to zupreem pellets and now that he has been eating zupreem for two years he's back to his old picky ways and not wanting to eat his roudy bush. I was wondering if anybody had any tips or ideas on how to get Charlie to start eating his food. He's picked up the pellets a few times but then just drops them and I have two bowls on their cage full of roudy bush mini and crumble pellets.

Harrison's Bird Foods
I feed Harrison's, supplemented by fresh healthy treats. My first, and later, my current avian vet recommended it. 30-ish years ago, Harrison's was still a small company. My vet was actually able to talk to Dr. Harrison about my bird's species and status, and they decided on the High Potency. My bird loves the pellets now, but to get him converted, my avian vet suggested putting pellets out all day, and putting seeds (his old diet) out for two 15-minute periods a day. That would sustain him but leave him hungry enough to try new stuff. I presume the same technique could be used to get him to eat other healthy stuff. My guy was eating pellets in a couple of days, and now I can feed a good variety of other stuff, knowing he has the pellets as a basic. Pellets are out all day... fresh treats a few times a day. I also like Harrison's via mail because I never have to worry about out-of-date products.

What works for me and my JoJo, I only introduce new foods on his play stand. Normal first reaction, I get the evil eye, and the new item is spit at me! I immediately remove the rest. Second time, he will taste it and walk away. Third time, oh ya, my favorite!

Side note, for our children, we never put veggies on their plate cuz veggies are grown up food! Wifey and I ate directly from the main serving dish and the kids always wanted to sit on our laps and pick in the 'big girl' bowl!