I agree with you that it is unlikely that Obama would have been recognized at birth as a UK citizen due to lack of a documented marriage of his parents, so far. The claim of marriage in Stanley's divorce filing is hearsay.
Obama II would never be removed as POTUS without finding the marriage license or other contemporaneous documentation of the marriage. I don't think Stanley Ann's hearsay claim of marriage in her divorce filing (that Obama Sr never contested) would be sufficient grounds to somehow declare Obama II to be a non-NBC and removed from office, as Donofrio imagines.
Even if documents are found to substantiate the hearsay Maui marriage, the bigamy issue regarding Obama Sr's 1956 marriage to Ketzia would have to be legally assessed.
Whether an unmarried US citizen mother's baby can be NBC under the constitution (even if the natural father is a non-US citizen) could likely only be decided by SCOTUS.
Perhaps that is why Fukino declared Obama II an NBC knowing there was no legal marriage of the parents on record in HI. She might have been advised to conclude that even if Obama Sr was on the BC as the father, with no marriage license of record, there was no dual citizenship issue. Fukino has the marriage vital records as well as the BC records in the same department, I would think.
Perhaps only if Stanley Ann and Barack Sr were married in Kenya in some manner that conferred British citizenship to their children, perhaps in a legal polygamous tribal marriage and then Stanley Ann returned to the USA and gave birth to Obama, then Obama II might be removed for not being an NBC due to dual citizenship. (My brain hurts). It seems to me the only hope for a clear declaration of non-NBC status that US citizens would understand and support and the only realistic political threat to Obama II is validation of a non-US BC such as either of the complimentary Orly and Lucas BC's.
It is a convoluted mess. When devising the argument, you have to go with the known facts and known law, find your counter argument if it doesn’t fall in line with what you want (but you can’t totally ignore the law).....and then bring in how each possible variation of detail would effect the analysis.
It is an incredible mess..before you even get to the Indonesia aspect of it.
As for the Kenyan marriage...there is a UK law about marriages before 1971 or 1972. That is another wrinkle to the whole mess since Ann was domiciled in the US.
I saw someone state on another site that being white would effect the customary marriage part of this as per Kenyan law. I don’t remember if I looked at that law or not. There is a Kenyan law website where you can read the old laws.