Barcelona is even bigger than that isn't it? Their wage bill is miles above the league imposed wage cap based on their finances so even if they took on debts to buy him they wouldn't be able to register hm without some huge changes in their finances. Real have a similar problem which is probably the biggest reason why mbappe never moved.
On Martinez I know he's only been here a season but I feel more confident in him than any other keeper I've seen for us, he has the perfect mix of attitude, ability and personality to be a world class goalkeeper and things like saturday are just a reflection of that.