Name Nl is Schippersdok :

https://www.anderlecht.be/sites/default/files/medias/Files/tourisme/decouvertenl.pdf
https://port.brussels/nl/vrije-tijd/interactieve-kaart

It's also not a dock : waterway=dock

I have a big doubt that this tunnel have a name (it is not signed by the way) and the "alt name" make reference on a historic zone "petite île" that is not in this side of the Senne ... railway=abandoned is also suspicious according the height of it. More research needed.

Double is more than probably not the name of the building , but the interpetation / transliteration of a newspapper. Inauguration signs on the ground talk about "his double" in fr and in nl Dubbelganger Project.

Already discussed in changeset comment : changeset/116516724
But Ground signs and local don't name this building like this.

This is not a pedestrian area here : https://www.mapillary.com/app/?pKey=167515749350780

And also not on Place Rogier : https://www.mapillary.com/app/?pKey=178978577870675

Sign = F12a = all the zone is 20 km and bicycle are allowed