Theravada Buddhism was brought to Burma and Thailand from Sri Lanka in the first century CE. See, #17 of “Preservation of the Buddha Dhamma”
So. Yes. The Europeans found copies of the Tipitaka in several countries.
– But they also found Mahayana documents AND Vedic documents too, especially in India.
They had no idea how to sort out all those things.
Furthermore, Buddhism had declined in all those countries. In fact, there was a revival of Buddhism AFTER the Europeans got interested.
– You should read the book “The Search of the Buddha” by Charles Allen (2003).
– That book is mentioned in #7 of the post, “Misinterpretation of Anicca and Anatta by Early European Scholars.”
– Those days, most Asian “scholars” went to universities in European countries to study Buddhism! It was European scholars in those universities (including Prof. and Mrs. Rhys Davids) who made the critical decisions on how to interpret verses in the Tipitaka!; see #11 of that post.
By the way, I am working on your other question on Tirokuddha.