An update on the Europe-gig: some names have been confirmed: Arno, Axelle Red, Clouseau and Simply Red. No Tom (yet?).

Some more info on the Europe-birthday-gig in Brussels: apparently each country will be sending a big shot. First names are Julio Iglesias (Spain) and Eros Ramazotti (Italy). I haven't found any confirmation of the other names yet, but The Scorpions (Germany), Bryan Ferry (United Kingdom), The Corrs (Ireland) and Yannick Noah (France) are said to be performing there too.
As mentioned before Tom Barman/dEUS and Arno are rumoured to be the Belgian acts.

I have some doubts about Bryan Ferry because he has a gig in the UK the same day.
The website about the anniversary mentions the gig and tells us it will be screened on television.

On March 24th there's a big event in Brussels to celebrate the 50th anniversary of the treaty of Rome. There will be a concert near the Atomium in Brussels. There are strong rumours that Tom Barman and Arno will be performing there. I'll keep you posted.