Does the deck ledger board always need to be flashed even if bolted to a solid masonry wall?
All ledger boards should be flashed to prevent top of wood member rotting over time since it never drains properly. But as for brick also - water still is a concern seeping behind the ledger board and getting into the brick and deteriorating it over time. Some installers just silicone caulk the top of the ledger where it meets the brick wall. But that eventually dries and cracks. Original Installer may have done that.
Does flashing matter when you’re not supposed to bolt through brick in the first place?
Page 15
http://www.awc.org/pdf/codes-standards/publications/dca/AWC-DCA62012-DeckGuide-1405.pdf
The OP state it is a solid masonry wall and not a veneer brick wall. With this assumption, the deck can be attached with proper bolt type. Todays standards prefer a floating deck since most houses are brick veneer and not solid masonry.
OP has to clarify ‘solid masonry’
If it is a veneer - hopefully the ledger is bolted thru the veneer wall and into a solid structure of the house to have some vertical load support BUT this still isnt acceptable since the gap in between the veneer wall and the veneer wall not being structurally supportive for the ledger , causes great vertical load on the bolts. They can bend or snap.
There are a lot of solid masonry homes here. Reading the code it says masonry, hollow masonry…not solid masonry. Finished basement can not see bolts.
Kevin gave you good information here. Look at figure 17 on page 15. 
What is age of home- early 1900’s usually solid not veneer , any header type bricks in wall to show solid brick wall tied into interior brick wall.
Any weep holes = veneer
Window and doors have lintels or brick arches. All ways to possibly ID as veneer or not.
Home built 1954
Looking back at ur foto, there is a row of header bricks in lower portion of foto, which offers a better probability that it is Not a veneer wall
Agree…thanks for the additional photos….I missed that course in the 1st photo.
Solid masonry wall. Just report no flashing observed as is recommended etc. Not many ever are, shocker 😜
Here are 2 foto / diagrams that show the best method if you wanna keep in your library for reference.
Thanks
Much cleaner look and durability…
Thanks
Nice Chris