It's definitely Botulism. Since your chick is younger, & smaller then an adult chicken, incubation period can be shorter then within 2hrs - 2 Weeks.
There's a slight possibility it could be from Mycotoxiciosis, which is from eating mold, & has similar symptoms as botulism.
In gamefowl there's Baby Stag, which is what he's considered, then he'd be a Stag when older, around a year he'd be called a Bull Stag, years 2, & over are a Cock.
How old are they exactly? They could be Rose Combed OEGB which are super rare, or someone's Black Sebright project.
I would say rose comb bantams like originally, but they don't have the white earlobes.
I'll get pictures of my shrimp tailed hen. She's on the smaller side, smaller then her mother, but that doesn't mean she won't give big offspring.
I have her, & her mom in hen Saddles currently, to help protect the new feathers regrowing on their backs.
Could offer the chick some scrambled eggs, or raw yolk as it has riboflavin, & other vitamins that may have until you can get the rooster booster. You can continue with the Nutridrench as well while waiting.
Here's Big Blue. He refused to stand pretty, so he's not showing his full size. Standing fully he's at 3ft if not alittle over 3ft tall.
He's still regrowing in his tail. It'll be beautiful once he's completely done molting.
But what's the name? I like looking up the nutrition facts, & ingredients to determine if its a good feed, or not.
Cut out the snacks for awhile, it's more then likely due to a deficiency, so it'll need vitamin therapy. Do you have any Rooster Booster Poultry Cell?
Manna Pro is a good feed...