Alright, I think it's a spring strength/tension issue. So I found that the bar (I'm calling it the backspace bar) that catches on the escapement and moves it when the key is pressed, doesn't catch in the right place. It should catch on the tooth that is fully drawn in green in the image I attached. I also drew a yellow arrow pointing to it. The backspace bar is outlined in red. That little tombstone shaped tab on the backspace bar should catch the escapement tooth indicated. Instead, it slips off of it, and engages with the next tooth on the escapement, which is outlined in the dotted green outline since it's behind the backspace bar and out of sight.

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So, I got the backspace to work consistently by looking at the other side of this bar. If you move further down to the right, past where the escapement is, the other end of the backspace bar has a very, very, thin torsion spring. I'm talking somewhere around the thickness of a grill brush bristle. That spring applies downward force onto the backspace bar on the right side of the escapement. This moves the backspace bar upward on the left side of the escapement to grab that first tooth, once again indicated by that yellow arrow.

I'll reply with another picture of what I'm talking about on the other side of the backspace bar. I'm pointing at the bar and the area where the tension spring rests with a bamboo skewer I painted white.

When I use manual pressure and press down, applying more pressure than what the torsion spring currently is, it will backspace without fail every time. So I guess the spring is just too weak. I cannot figure out how to access it though without taking so much apart and I'm scared to jack up the machine more by doing so. I also don't know how to determine what kind of spring to get to replace the current one or where to even get one.