Both for and to are required. Personally, I would accept the second one without the to , but I don't think most people would. The "rule" is that you have to have the preposition in the subordinate clause when the object of that preposition is being relativized.
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Marius Hancurelativized.As in the examples. The noun at the beginning of each example is 'being relativized". These are the antecedents of the gaps at the end of the expressions where the same word would go after the preposition.
Care to translate, CJ?