I would also be dissappointed - undoubtedly but that is also a reaction to how anal we are about our cars in many ways, the Vee especially ... They may be at fault, I said not always Renaults fault, if you can justify that they are culpable having done the work recently then you may be able to negotiate ...
Interesting though as I have to admit that whenever I took my car for servicing I always checked the engine cover bolts and under the engine covers etc. etc. in the car-park before I left ... On one occassion Renault had left some of that blue paper towel on the exhaust ! But I just went into the service area and asked the service manager what he thought of his teams standards ...
IMHO the more anal we are, the more responsibility we have to take for maintaining the perfection but the more dissappointed we are if others don't come up to our standards ... I was the same with my Vee ...
If it was me personally I would drill and tap the holes myself as I wouldn't trust a dealer to do it - even if I could negotiate them to do it ... I would do this even if I snapped one myself as I also don't like cable ties where they shouldn't be ...
Martin