Unsure of the role of these transistors while reverse engineering a keypad PCB
Chances are the '24' transistors are DTC114ECA prebiased transistors (10K + 10K).
'G1F' is probably BC847B NPN transistor. Unlike those of the prebiased persuasion, those will need base resistors or you'll burn out the transistor if you apply much voltage wrt ground. One of them obviously drives D2 LED and the others probably something similar off of JP3.
It's generally a good idea to put 1K in series with one side of whatever you're probing with.
That should be enough for you to figure out the schematic.