So I would interpret this a bit differently than "MD 896 is unsigned". Sure, there are no MD 896 shields posted (can confirm this having driven it), but MD 896 does not exist in a vacuum - it is part of multi-state DE/MD/PA 896 with the DE and PA portions being well-signed. Looking at it as one continuous multi-state route, it is to be expected that there are no 896 signs within Maryland as it is a stretch only 1100 feet long with no major junctions. There are countless sections of signed state highway that go a much longer distance between reassurance markers where we don't notice or care because no state lines pass through them.
I would make the argument that MD 896 warrants being included/left in based on the above, for the sake of continuity between DE 896 and PA 896.