There is a lot of strange stuff going on with these shields.
I think that that whole entrance is wooden with glass panels, and that the shields are wooden as well.
All 4 shields are of a different shield shape, which is in itself strange. When multiple shields are displayed, they usually have the same shape.
A - Very early English shape, first designed in Dereham in Norfolk. The chevronells are not equidistant as they should be. That could be a Post Horn, or light cavalry horn in the base. A lot of extra studs for decoration.
B - Shield is a European (possibly Germanic) shape. "Four crescents in cross horns outwards". This is possibly the most accurate of the 4 shields.
C - A fanciful Romantic shield, again European. "A fret cloutee." That means it has nails. The fret is too low down the shield. It has been lowered to fit the shield shape. This is wrong. The cross in the middle of the fret should be in the middle of the shield.
D - A fourth shield shape, later English. Two swords in saltire piercing something with a fifth shield (blank) overall in base. If at all possible, the fifth shield must be the same shape as the fourth shield that it is on and must be central. The fifth shield is of a design used for marital arms (man and wife together)(marital arms are not placed on another shield).
All in all, I think that these shields were put together by a local craftsman who knew precious little about heraldry. I would not be surprised to learn that none were granted by either the College, or by Lyon Court. With the exception of B. It has a Scottish look about it.
I will do more research.
Regards
Chas