I just saw this. (See my answer above.)
Toot (gay male) rhymes, more or less, with English “toot”, while Tot (fart) rhymes, more or less, with English “tote”. Siam Sam might have conflated with Toot meaning buttocks, but that is yet a third word (longer vowel, different tone.)
Curiously, all three of these words begin with unaspirated “T”, sometimes transliterated “Dt”.
Even ignoring tones, Thai has a plethora of easily confused vowels. And consonants like the unaspirated T or unaspirated P are hard for non-natives to distinguish.