On the eve of the October election last year, the then candidate Bolsonaro was about to ask him to be his vice president. But he decided at the last minute to appoint a military man, the general in the Hamilton Mourão reserve. The change of decision was due to the existence of an alleged dossier with photos of Bragança in a gay orgy and his alleged participation in actions of an extremist group that went out at night to beat up the poor who sleep in the streets. Someone recommended Bolsonaro not to take risks and avoid possible future scandals. So it was. The ultra-rightist candidate put aside his claim and closed ranks with General Mourão, with whom he assumed power earlier this year.
I agree Marengo. There have been a few cases of non-reigning royals getting involved in political parties and elections (e.g. King Simeon becoming Prime Minister of Bulgaria and Archduke Karl of Austria being president of the Paneuropean Union), so it's not the first time someone in Luiz Philippe's position has gotten involved in politics. Non-reigning royals are essentially private citizens and have no official role in their countries, so it's totally fine for them to branch into politics if that's what there interested in IMO.
bit of a wait to announce. 
