Possible Clues:

• Carson's act, funny and above criticism
• A cross can't be played with — it's very holy
• Aristocratic, like Eliza Lynn Linton's Ms Kemball?
• Can't mess with a cross that's this
• Beyond criticism
• Co-stars can (anag.)
• Untouchable Costa Ricans want one badly
• Too important to touch
• Misguidedly scorns act archbishop initially finds inviolable
• Unimpeachable as other clues here are, last one starts with absurd cant