Hi, and welcome to the forum.
You should keep the new cat in a room away from the other cats for awhile (I did this for almost two weeks). Of course, have food, water, litter box and a bed available. This helps them to feel secure, and prevents serious fighting with the others. This also helps prevent potty accidents since she knows right where her litter box is.
Spend lots of one on one time with her so she gets to know you. I know of some people who put a sock on their hand and pet the new cat, and then pet the other cats so they can get used to each other's scent. I am sure she is just scared. Go slow with the introductions. Hissing and swatting is common at first. Make sure all cats claws are trimmed. I wouldn't leave them all together unsupervised until you know that they are tolorating each other.
Bengals are vocal cats. She may be a little more vocal right now because of being in a new home. Bengals love attention and "ask" for it often!
Just be patient with the introductions, and take your time. I am sure it will all work out.
Good luck with your new cat! You will love owning a Bengal (or should I say your Bengal will love owning you)!