Yes, you have repeated that story several times. “Bulgarian couple” does NOT mean “innocent or non-threstening”. (But it does a wide variety of other cultures who DO threaten, intimidate, and assault. (Imcluding Gypsy. Muslim. Turkish.)
Correct, it could mean any of those.
What is isn’t is an African, Arab or Pakistani accent.
Beyond that the online narrative is building up a whole series of stories, none of which are verified. Better not to speculate