Probably. Sounds like something Support could help you with.
But if you have control over the domain name, and the nameservers are pointed at Dreamhost, just cancel the parking on one account and enable it on the other. I think, theoretically, anyone with a Dreamhost account can host anyone´s domain if the nameservers are pointed at dreamhost and no one else on Dreamhost is trying to host it. Or maybe that´s just my naïve understanding.