2018 zafira tourer with 110000 miles on it serviced requarly with oil changed every 10000 timing chain snapped inside engine according to everything what i have heard and read the chains are supposed to last the lifetime of the car.

this timing chain is a non servicable  item does this mean it would be still under a warranty of some sort

You could try to argue this with the dealership but doubt you'll get far.
Timing chains tend to break across a whole range of vehicles and although they should be lifetime (e.g. 100k miles which used to be a vehicle lifespan) they aren't that durable