The episode mocks Jennifer Goines' inability to use pronouns and verb endings correctly in Early Modern English... and then the script goes on to make exactly such errors, even in native speaker's dialogue. "Thou" is a subject form; "thee" is an object form. "-est" is an ending for the "you" form of a verb, while "-eth" is for the third person (he/she/it). It's not hard to learn, or to find someone with the minimal grammatical knowledge to get it right; it's a shame the scriptwriters couldn't be bothered. See more
It was a machine. We didn't get a chance to figure out when it was gonna send me. The beginning, the end...
It doesn't matter. Olivia's the center... A Djinn created by time travel, no true beginning, no true end, and thus unbreakable. She's our demon.