well, that's scary. at least it sounds pretty clearly like a bug though, so, if no one has any savior suggestions, i'd gamble on regression issues getting patched soon. i'd suggest making an extra copy of your last stable backup and then try opening the map for the next patch or two to see if its spontaneously better, as Blz fixes things on their end. You can double check that a backup is working as expected by playing it without opening/saving it in the editor first. If you can open the map without the glitchiness you're seeing, then you're good to go
my only other suggestion is a headache. you could also try using an mpq editor to open your map's doodad file and then iterate removing half the doodads -> check if glitched until you find the doodad(s) that are problematic. you probably don't want to use the world editor to remove doodads in this case, since the editor might be contributing to the issue, and saving the glitched state in the editor might not be recoverable by deleting doodads. also, if you do this, you should start by just removing all doodads and seeing if that fixes it, maybe the doodads are just casualties of war