Your document claims its encoded using iso‑8859‑1, but that's wrong.

Judging by the repetition patterns when viewed as iso‑8859‑1, it's actually encoded using a multi-byte encoding such as UTF-8. iso‑8859‑* are single-byte encodings.

The most likely encoding would be UTF‑8. However, when viewed as UTF‑8, you still see the telltale repetition pattern of a multi-byte encoding.

I suspect you did the equivalent of

print(encode('UTF-8', encode('UTF-8', $s)));
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