I looked around a bit and think maybe you got a couple old maps criss-crossed in your mind. On several maps, there is an area north of Semberholme in the Southern Part of Mistledale called the Barrowfields. These are human burial sites however, not the old elven crypts of the Vale of Lost Voices.
The Barrowfields: Located at the western end of the dale, the Barrowfields earn their name from the dead warriors buried in the long lines of low, grass-covered hills throughout the area. The ancient Netherese wizard-warrior corpses here have a disturbing tendency to manifest unusually deadly undead powers.
Your maps look great. Only one real problem, as far as Realms cannon material: the Vale of Lost voices was located in the Southern part of the Tangled Vale across the River Ashaba to the East, not to the North of Semberholme. Did you draw your map by hand or use some program for it?