A BELGIUM KING OR FORMER KING HAS NEVER BEEN BROUGHT TO JUSTICE IN BELGIAN HISTORY

In this Vanity Fair article from the January 2020 edition, writer Erin Vanderhoof, which came out before the decision, it says that Dephine would not receive a title or be in the line of succession to the throne.  I think that she is now a Princess but prefers not to use a title and it's true the succession was not an issue between her and her birth father's family.

VANITY FAIR BELGIUM KING ALBERT II DNA TEST PATERNITY 

 EXCERPT:  Longchamps (i.e. Sybille de Selys Longchamps) claims that Albert was not furious when she became pregnant, and that he even sent flowers after her (giving)birth. "It was a beautiful period," she said. "Delphine was a love child. Albert was not the father figure, but he was very sweet to her."

(The legal wrangling went on seven years.)

It doesn't necessarily end all of the legal wrangling: Boel may still be entitled to a portion of Albert's fortune that has been estimated to be worth hundreds of millions of dollars.  But it does end the portion of the case that might have had a constitutional impact had Albert refused the test, because a king or former king has never been brought to justice in Belgian history.