You call every guess you make a hypothesis, in a transparent attempt to give them credence, or some form of credibility. However, a hypothesis is simply an assumption, in other words, a guess.
Your hypotheses do however all share a common theme; to lay the blame entirely with the motorcyclist, and completely exonerate the truck driver. Your prejudice against foreigners in Thailand is palpable, both here, and on other threads; so, as noted earlier, with that kind of bias, we are all fortunate that you are not an accident investigator.
Your claim to have driven extensively in Thailand is completely irrelevant to this tragedy, and is just another feeble attempt to give some credibility to your extensive guesswork.
And please stop shouting at me using uppercase font; it is very rude to shout at people ….. many thanks