I was having the same problem with this episode too (and a lot of other content for Japanese in netflix), which lead me this bug report.
Deleting some words fixed it for me. I can't say exactly which words cause the problem but I deleted all words that start with hiragana or katakana characters and the word 高校 (this word wouldn't let me parse the subtitles for the movie "whispers of the heart"). Hope this info helps at least a little bit.
Latest posts made by Anon 1mp
RE: Unable to parse Netflix-jp subtitles of the first episode of Laid-back Camp. Extracted "bad" & "fixed" srt files provided for testing.