some cores like the repack i have is 3.1.2 compatible but doesnt have Ulduar in its dbase SO i personnally searched web sites for hours for the xyz and found one that put me in the mountains. after doing some gm flying i found the start, inside and yogger's brain room
the coords for the Iron Council is
X = -887.326
Y= -148.702
Z= 458.86
O= 6.26746
on MapID 603
Once there just do .tele ulduarraid1 so u dont have to save these coords
Ill post yogger's brain when i go in to get them. If ur erger to see is brain room then just fly outside of the instances where u see alot of screwed up texting and fly way down and go way below his prison then just space bar up, his brain room is right below his prison