Is there a way to create multi sig adders without all private keys?
Sure, public keys is the only need.
Similar to the way to private keys can sign the raw tx separately?
Yes, separately.
Is there a way to independently verify how many signatures the multi sig address requires? For example say 3 partners want to do a venture and they do a ./bitcoind createmultisig 3 ... Can each partner verify that the address does in fact require 3 signatures?
The information can get from the redeemScript, when you create the address.