ED could be wrong.
they was wrong with DGFT Alttitude Awareness Arc not included in this block 50.
new nadir/zenith, bendy dive pitch bar, ghost horizon, extended horizon bar, all come together with same software upgrade SCU-2 1993 (after block 50 1990)
and i think block 50 got this upgrade too (DCS simulating all except nadir/zenith)
i don't have USAF -34, is it refer to DGFT arc, bendy dive pitch bar, ghost horizon, extended horizon bar ?
i doubt if that -34 cover all software upgrade change (MLU, SCU).
if they was really removed only nadir/zenith from block 50
only reason i can think of, is almost all test pilots not prefer and rarely use it, as they complained in that report.