S204 Airbag recall

[focusxr5]

I'm after a little bit of advice. My S204 was recalled for the earth to the airbag. The work was done back in February by MB Sunderland. I went to work away the day after the work was carried out. I have recently returned and found that there is an irritating squeak from the steering wheel due to the cowling rubbing on the back of the steering wheel. According to my OH it's been like that since the recall, during which the cowling was removed. The problem is that my OH has continued to use the car regardless and has now racked up 6 months and about 8 thousand miles since.

It's irritating the life out of me. Will Mercedes carry it out as a fault rectification following their recall or am I looking at a bill? It's not the first issue around squeaking cowlings following the recall that I've heard of.

Thanks