Select2 change value from jQuery doesn't work (dataAdapter)

How Do I...
#1

I have a huge json data source (over 50,000 + lines) loaded in memory from a static file.

Note: It’s not important why I have it in a static file.

I use select2 (v 4.0.5) that initializes as:

function initSelect2(selectName, dataSelect) {
var pageSize = 20;

    $.fn.select2.amd.require(["select2/data/array", "select2/utils"],

        function (ArrayData, Utils) {
            function CustomData($element, options) {
                CustomData.__super__.constructor.call(this, $element, options);
            }
            Utils.Extend(CustomData, ArrayData);

            var initialValue = { "ID": 17003, "C": "200779", "N": "clanok baterie 2pzb150", "SC": 1 };

          
            CustomData.prototype.query = function (params, callback) {
                if (!("page" in params)) {
                    params.page = 1;
                }

                var data = {};

                if (params.term != undefined && params.term != '') {
                    let subData = $.grep(dataSelect, function (n, i) {
                        if (n.text.indexOf(params.term) > -1) {
                            return n;
                        }
                    });

                    data.results = subData.slice((params.page - 1) * pageSize, params.page * pageSize);
                }
                else {
                    data.results = dataSelect.slice((params.page - 1) * pageSize, params.page * pageSize);
                }

                data.pagination = {};
                data.pagination.more = params.page * pageSize < dataSelect.length;
                callback(data);
            };

            $('#mySelect3').select2({
                ajax: {},
                dataAdapter: CustomData,
                width: '100%'
            });
        }); 
}

I have one big problem. I can not set the value to select from jQuery. If I try like this:

$ ("#mySelect3").val(17003).trigger(“change”);

nothing will happen. But I think I’m doing it badly. If I understand the documentation I think I should implement function:

CustomData.prototype.current = function (callback) {}

that should create the data, and then function:

CustomData.prototype.query = function (params, callback) {}

should only filter them.

Can you please help me, how do I implement select2 initialization, that can work with many options and can by set from jQuery?