Did France also attack the Channel Islands?

Did the French try to invade the Channel Islands during the war?

Yes, but the islands were strongly defended and their separate status does not displace Fishguard from the usual last-invasion claim.

French forces did attempt attacks on the Channel Islands, whose strong defenses made them difficult targets. The islands are British territories outside Britain in the geographic definition used for Fishguard's last-invasion claim. Attacks there therefore belong to a different geographic category from landings on Britain itself.