Slowly making progress. I called a couple of days ago because the person would call me back with the results of his investigation, didn't. Just when I was making my way up to go and do some shopping, and call VM to enquire, I got a call regarding my still open problem.
Now things get moving

!!! My second account gets closed (broadband + phone at my neighbour's), and the phone will get transferred to my address (broadband only, and disconnected phone). The person couldn't do it, because he wasn't sure how to do it on the computer (wasn't his daily job, so no prob for me), but I got the choice between a new number immediately, or wait till Monday till the appropriate people where in, who normally do this, so I opted for the latter.
Next is obviously seeing that I get my money back for the second account