This save has 17 units which show up in Dwarf Therapist 20.4 as living units. (They do not show in 6.12; if this helps)

All dwarves are in a squad so finding the dead units is as easy as listing by squad in DT.

Pick any unit; example Zaneg Inethrober.

'S'earch the name out in corpses from stocks screen and zoom to the body to find his partial skeleton.

He is definitely dead and buried while DT lists him as living.