Hello,
Indeed modifying the "Promenade verte - Groene wandeling" hiking relation was not my intention. When detailing the cemetery entrance, I moved some footways/roads belonging to it in order to square the corners, but this should not be an issue. 
The only change made was dividing the way 811279632, to create a crossing and then a second sidewalk, but I double-checked to be sure that these new ways would still be part of the relation. 
And, when I checked the relation before approving my changes, it seemed to be connected, without any missing element.
I'm sorry if something went wrong, and let me know if there's something I can do to fix it.