Those are some very excellent points you make, Mk1. Your input is very much appreciated.
Back to the game.
We are still on Turn 2. Here are some more pictures showing the action against the lone Panzer III on the hill.

The range for the 3 Russian tanks firing is 13 inches - give or take. This range incurs no penalties or positive modifiers.
The Russian TQ is 10. If this were a straight shot, they would need a 10 or less to hit. HOWEVER. The German just moved in his last turn so still gets a -1 applied for that. In addition, the Russian has a -3 penalty applied for being at a higher elevation. There are no other modifiers that apply to the target in this case as the Panzer III has a DM(Defensive Modifier) of 0.
Since the Russian is only firing and not moving at all this turn, he gets the OM1 modifier which is 0. If any of the T-34s move using their bonus move, that tank would drop down to OM2 which is -4 for the T-34.
As it is, the Russian needs a die roll of 6 to hit the Panzer III.
By the numbers:
TQ = 10
Range = 0
Target Moving = -1
Target at Higher Elevation = -3
Result is 10 - 4 = 6. This is the number or less on a 20 sided die needed to hit.

The first tank shoots and rolls a 10. This is a clear miss.

The second tank shoots and rolls a 12. Another clear miss.

The third tank shoots and does score a hit with a roll of 3.
Now we go to the Kill Table to determine any damage to the target.

Here are some of the stats for the T-34. Its armor piercing round (AP) is rated at 9.

Here are the stats for the Panzer IIIL/M. On the right side of the chart you will notice that there is ratings for F/S/R/T which is the Front, Side, Rear, and Top armor ratings. This is clearly a frontal shot so the 7 armor rating is used.
If we compare the AP of 9 to the frontal armor rating of 7 there is a +2 differential. Before going to the Kill Table there are some other possible modifiers to determine the actual row to use on the Kill Table.

Here is a closeup of the AP modifiers table. At a range of over 12 inches to up to 24 inches the Russian suffers a -1 penalty for Low Quality Ammo. The Germans have High Quality Ammo but the Panzer IIIL/M will suffer from having a 50mm gun in the Less Than 57mm Section.
Based on that, the Russian will roll on the 1 row of the Kill Table to determine his damage.

Possible results range from 2 hits with a roll of 1 all the way to no effect.

A result of 17 means No Effect. The round has either glanced off or else hit a non critical area of the tank.
A very lucky break for the German.