The education record is nothing but a clumsy amalgum of the records of two seperate individuals. You really need to take a much closer look at the detail.
I see nothing “clumsy” about the two transcripts from state universities in HI and WA and nothing to support even a suspicion that two separate individuals are involved.
The WA transcript incorporates Stanley Ann's HI credits from the fall of 1960, shows her to be a graduate of Mercer Island HS, but shows her as a nonresident of WA consistent with her having changed her residence from WA to HI in between HS and enrolling in U WA.
The dialog in “Dreams” supposedly recounting Stanley Ann's own words including dates and age that would place her in Chicago in 1958, are in the voice of Bill Ayers, not BHO II and simply cannot be relied on. Stanley Ann graduated from HS in 1960 and was not reported in any accounts to be pregnant at any time before graduation in 1959, as you have suggested.
One would think that witnesses would have been found in Mercer HS if Stanley Ann had been pregnant there or given birth to a mixed race child.
One witness has SADO arriving in WA with a newborn and and another witness who babysat for Barry while SADO was taking classes has taking an apartment in her building in early 1962 in WA with a six or seven month old infant.
The major mystery that I see remaining is the location of SADO between the her marriage to BHO Sr and her arriving in WA, during which time BHO II was born. SADO crossed at least a good part of one ocean with a newborn to get from HI to WA, but was there only ocean that she crossed and when?