I want it to be hidden and at the same time easy to find.
It should not be in a place that is too visible, but I want the user to find it when he is looking for it.
It might help if you could put up a rough visualisation of your proposed design, because without it, it will be very difficult for the community to provide suggestions.
However, the bottom line is you want people to actually use this feature, otherwise it will be a waste of money building it. So you really need to consider the utility of this link and how easy it is to find it.
One approach for you to consider when a user first comes to this page - how about implementing an on-boarding mechanism which flags this link (wherever you place it) and provides a brief explanation as to its purpose.
In terms of this link's placement, I would would guess that Trouble Reporting would not be needed most of the time, so the link should be placed much further down the information hierarchy of the page, so that it does not interfere with the primary feature of the page.
Without being able to see your proposed design, I would guess that the bottom right-hand corner of the page would be good, because the corners of a page are prime positions.
If you have a footer in the application, I would personally place it in the bottom-right of the footer, because this ensures it is visually separated from the rest of the page, while at the same time its corner position ensures it is always easy to find.