The French fleet lacked time and fuel to escape Toulon

Could the French ships at Toulon have escaped to join the Free French instead of being scuttled?

Not at the moment of seizure; they lacked the time, fuel, ammunition, and readiness needed to get away.

The immediate barrier to escape was readiness rather than a lack of possible destinations. German restrictions had stripped fuel and ammunition from the Toulon force, leaving the ships unable to get under way when seizure became imminent. Large fuel stocks were captured after the scuttling, but they were not available aboard the fleet for a coordinated breakout. A successful escape would require an earlier warning and preparation window rather than a different last-minute order.