Why doesn't my regex match text with $ character in it?

Question

I'm using preg_match_all() to search for some custom markup in a user template. However, the function isn't matching strings that contains a $ character.

The template tags can take two forms: [TagName] and [TagName|some text here|some other text here].

Here is the regex that I'm using:

preg_match_all('/\[([^\]\|]+)(\|)?([^\]\|]*)\|?([^\]\|]*)\]/',$thank_you_screen_text,$thank_you_tags,PREG_SET_ORDER);

These strings all match:

[Name1]
[AddTour|Yes!|no]
[NumberOfPersonsForRoomOut| x 2889 =|          ]
[CardholderName|Cardholder's Name:|]

However, any string with a $ character in it fails. It will not match the string at all. These do not match at all:

[NumberOfPersonsForRoomOut| x $2889 =|          ]
[NumberOfPersonsForRoomOut| x \$2889 =|          ]
[RoomSubtotalOut|\$|]

I've tried it out using the Regex Tester at regex101.com and it works there. What am I doing wrong?

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The above results are on a server using PHP 5.5.22 with PCRE Library Version 8.34 2013-12-15.

However, I tried it on a couple of other servers, and everything matches as I would expect! The other servers are PHP 5.5.38/PCRE 8.38 and PHP 5.5.15/PCRE 8.34. It doesn't seem to be the version of PCRE that is the problem. What else could be causing this behavior on a particular server?