Indicator switch is known error supposed to die after 5 - 7 years in 207, in ur case you are lucky it lasted 10 year. 106 aed new indicator from Swaidan guys.
Thats interesting, im surprised how did it happen?
I guess try with some screw drver from latch side, but looks very difficult. Better take to some denter guys who can dismantle the door and open the child lock and refix the handle.
Not really if you have change the Piston rings, crank bearing, connecting rod bearing etc too then atleast 1000 km running in must.
Only head gasket sets in half an hour of first drive. Still better drive easy for first 100 -200km. thats it.