Yo can you supply a source for a scratch not being possible in caliborn's session?
It hasn’t been stated in story that it’s impossible, but the Cali’s weren’t made through ectobiology and Caliborn’s session didn’t have a Reckoning so a scratch wouldn’t change anything. Also he doesn’t have Echidna as a denizen or have Needlekind so he wouldn’t be able to initiate the scratch regardless.