Yes to both questions.
Per Jamil in his article on Roggenbier...
Jamil in Oct BYO
To develop color without adding roasty flavors, a little debittered black malt does the trick. My preference is for Weyermann Carafa Special, a huskless roasted malt. The lack of a husk means far less bitter roasted flavors."
He says that the regular Carafa has "a lot more roasted character"
The crystal malt may be a bit more caramel-ly, but will be a good sub.