So, rather than removing filtering completely, I have simply added the string “hellip” to the filter:
$short_caption = preg_replace("/[^A-Za-z0-9?! ] + (hellip) /","", $short_caption);
This replaces “hellip” with an empty string, which allows the ellipsis to return. In addition, it fixed an issue we were having with the “#” character being removed from embedded hashtags.