The reason I bought up Kamyuhn is because I theorize that Kamyuhn was NOT originally in Eva route, I believe she was edited in later when the route was already done.

there are two reasons why I think this is the case, the first one being there are unused rebel futuran sprites that I believe were used in place of Kamyuhn until they changed it,

the second one being that Kamyuhn doesn't show up in any of the Eva route endings, there's no mention of Kamyuhn at all in ending 7 and ending 8 stating that she went "missing" (they didn't want to change the CG so they did this instead).