People are able to cross the Rift (Shard hop), but under normal circumstances that requires sacrificing one's physical body. Neither Unukalhai nor Cylva are exceptions to this.

The only known exception is the PC, as they had a hole punched in reality by G'raha specifically for that purpose. G'raha himself is a partial example, having gotten around the "living matter" clause by binding himself to the Crystal Tower and partially crystallizing his body.