ghost shrimp are agressive towards other shrimp and will probably kill them. snowball shrimp are just like cherry shrimp but a different color variation so they are pretty easy to take care of. the beta might also be a problem. Most people say its hit or miss with betas and shrimp.
I believe the first person to respond said the ghost shrimp would kill them. So, putting them in the same tank with ghost shrimp isn't the best idea. Also, you must have a very well behaved betta if he doesn't eat your ghost shrimp. All the bettas I've know would make a quick snack out of the smaller shrimps.