Yes the wastegate is controlled by the N75 solenoid so it could well be the problem.
No idea on the price though, but I think the part number is - 058 906 283 C - which is a change over valve according to the ETKA parts CD, so sounds correct, but as I'm not overly sure of the location in ral life it's hard to be sure. It gives you somewhere to start checking with the dealer anyway.
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