Difficulty using Matching Regex

Since you have a list of codes, I would recommend using either contains or JS for this. Regex is for matching patterns.
So, suppose you want to select only zip codes that start with 900, then the regex will be ^90{1,2}[1-9]\\d+$, where the symbols mean the following:

• ^ start of the line


• 9 matched literally.


• 0{1,2}: Match either 1 or 2 zeros


• [1-9]: Match 1 character between 1 and 9


• \\d+: Match continuous characters between 0-9 (as many)


• $: End of line

This sequence will match 90111, 90011, but not 90001 or 91000. For details look here.
Unless you have well defined or extremely complicated patterns, I wouldn't recommend regex.
If you would like to use JS, add this code to the question where you are asking for the pincode:
Qualtrics.SurveyEngine.addOnPageSubmit(function () {
    good_pins = ("${e://Field/good_pins}").split(",").map(Number);
    pin = Number(document.querySelector("#QR\\\\~" + this.questionId).value);

    good_pins.forEach((num) => {
        if (num == pin) {
            Qualtrics.SurveyEngine.setEmbeddedData("exit", 0);
        }
    });
});
You'll need to store the all the pins in an embedded data called

good_pins 

separated by a comma and then branch them out if

exit 

is not equal to zero