Okay here goes the battle of AcornArchimedes! I'm not entirely sure this is going to work, but I do note that the garrison is still the same, so here goes nothing!
Cat attacks longbow. As instructed, with a LB defending, I promote to Barrage 2. Gets in 2 hits, dropping him to 4.6/6
Cat attacks El Cloner the longbow, dying with no damage
Cat attacks El Cloner again, getting one hit
El cloner defends vs. the 4th cat again, this time getting 3 hits in
Last cat promotes to barrage 1.
Here's where we're at after the catting
Okay there are 7 pikes left in various stages of health, and I have 17 knights to attack.
I promote the first to C1 Shock - he has 25.7% odds and.... dies without scratching the pike

Next guy gets the same and somewhat makes up for it - winning @ 25.7%!
C1 shock knight vs. 5.2/6 pike @ 25.7% - dies, wounding
C1 shock knight vs. 4.8/6 pike @ 42.4% - win!
C1 shock knight vs. 4.6/6 pike @ 44.8% - loss
At this point, C2 knights get pikes, and C1 shock knights get longbows
C2 knight vs. 4.0/6 pike @ 66.3% - loss
C2 knight vs. pike @ 68% - win
Now even the C2 knights get longbows
C2 knight vs. injured CG2 lonbgow @ 68% - loss
C1 shock knight vs. injured pike @ 74% - loss

C2 knight vs. injured knight @ 88% - win
C2 knight vs. axe @ 89% - win
C2 knights now get holkans, and C1 shock knights get longbow
C1 shock knight vs. longbow @ 94.8% - win
C1 shock knight (finally) kills Elk Cloner @ 95.1% - win
C1 shock knight vs. holkan @ 90% - win
C2 knight vs. axe @ 95% - win
no promo musket vs. injured longbow @ 95% - win
C1 shock knight vs. injured pike @ 92% - win
C1 shock kniht vs. holkan @ 99% - win
C2 knight vs. pike @ 99% - win
no promo knight vs. pike @ 97% - win
no promo knight vs. HA @ 99% - win
no promo knight vs. last pike @ 99% - win and
So odds say I should have won 16.72 of those 22 battles and in reality I won 16 - so odds just about in line with expected.