for whomever is interested, this is how I've done it. HTML:

<div class="card-body">
    <div class="row mb-4">
        <div class="col-3">
            <button id="createReport" type="button" class="btn btn-secondary me-3">Report</button>
        </div>
        <a class="d-none" href="orchestrator/createReport/SummaryReport.xlsx" download></a>
    </div>
</div>

JS:

var request = new XMLHttpRequest();
request.open("GET", "orchestrator/createReport", true);
request.onreadystatechange = function () {
    if (request.readyState == XMLHttpRequest.DONE) {
        if (request.status == 200) {
            document.querySelector("#tools a").click();
        } else {
            showMessage("danger", "Error retrieving Summary Report from server");
        }
    }
}
request.send();