These were detected by the fact the the SWORD filter algorithmic transliteration by ICU barfed at the invalid glyphs and had the following character in the transliterated words.
U+E03C <private-use-E03C>
To find these two bad glyphs, search the Gurmukhi text for PCRE pattern \x{0A39}\x{0A3C}
These previously undetected invalid glyphs are the sole two instances in which GURMUKHI LETTER HA is followed immediately by GURMUKHI SIGN NUKTA.
These were detected by the fact the the SWORD filter algorithmic transliteration by ICU barfed at the invalid glyphs and had the following character in the transliterated words.
U+E03C <private-use-E03C>
To find these two bad glyphs, search the Gurmukhi text for PCRE pattern
\x{0A39}\x{0A3C}