I would never defend anybody who departs with icing on the wing , but my question would be, what was the outside temperature when that happened.
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I have been flying this type of aircraft for some years but have never seen icing on top of the wing, due to cold soak(fuel below zero, but outside above zero, otherwise it would be frost rather than cold soak).
Underneath the wing on many occasions and if it is reasonably warm, say above 10c and you try to do a quick turn around , ridges of ice will form very rapidly.
Maybe it was condensation and if not, you should definitly report this incident to the company and maybe to the CAA , but would definitly find out first what temperature it was.