Maketrades According to him he was arrested and held in custody for 7 months, but then was let go because there wasn't enough evidence at that time.
Doesn't mean the investigation stopped, and perhaps now some more potentionally incriminating facts are obtained, hence the interrogation request. This might sound weird in some jurisdinctions, and actually is quite weird, but not in Belgium...
I still believe that person believes himself that what he is saying is true, but not making it true as already explained above.
In my opinin it is too dumb and low effort to be a smearing campaign, it wouldn't make any sense.