This is a case of delayed, not lost, luggage in which you are entitled to compensation of reasonable cost incurred while you were without luggage. Buying a clean shirt, or a suit if you really needed it and waiting for your luggage to arrive is not an option. I had my issues with KL/AF not honoring EU261 compensation for denied boarding/long delays, but never with claiming such kind of 'duty of care' costs. Of course some sort of receipt of such costs should be shown, that seems a quite reasonable question of KL/AF. Really surprised that your cards of 2 people (I assume credit and bank cards), were in the hold luggage while they fit in any wallet? That is a recipe for trouble (like here, delayed or lost luggage, but theft can happen too). I'd rather have my cc on me when travelling, if only for paying a meal or drink.