This apostrophe was actually one of a number of characters not removed by VaultWiki's UTF encoder, so it's possible that once it also has to worry about what the BB-Code parser does to the string it gives up on finding a title match. Either way, you can see I have fixed the encoding here on our site because your post above is autolinked.
The following characters were not handled and will be stripped starting in 3.0.6, with the exceptions of dash characters which would be replaced by hyphens.
Œ œ Š š Ÿ ƒ – — ‘ ’ ‚ “ ” „ † ‡ • … ‰ € ™
Please keep in mind that if any articles have titles with these characters and you didn't already define custom replacements, then you will have to rebuild URLs or use AJAX title changes to update the URLs individually. Otherwise, the affected articles may become inaccessible.