I wouldn't count on it. In my experience, no glue works well on plastic, even glue that is made especially for plastic.

By the way, does the front derailer on your Gitane have a chrome clamp and a metal cap instead of the red one as on a common Prestige? If so, it's the original and is rather rare. I saved mine by switching parts to an uncracked NOS Prestige body.

Please rerout those brake cables. It spoils the look of an otherwise beautiful bike. You got it right on your Raleigh.