Hi, try using this code. I included a way to show the asterisk, tested, and let me know if it works for you. 

/********************************************************************************
 * HELPER: Toggles required state + red asterisk on a field container
 * $field   – jQuery object wrapping the field's container (e.g. $('#q487'))
 * isRequired – boolean
 ********************************************************************************/
function setRequired($field, isRequired) {
    var $inputs = $field.find('input, select, textarea')
        .not(':hidden, :button, :submit, :reset');

    if (isRequired) {
        $inputs.attr('required', 'required');
        // Inject red asterisk next to each label if not already present
        $field.find('label').each(function () {
            if ($(this).find('.lf-required-asterisk').length === 0) {
                $(this).append(
                    '<span class="lf-required-asterisk" aria-hidden="true" ' +
                    'style="color:red; margin-left:3px;">*</span>'
                );
            }
        });
    } else {
        $inputs.removeAttr('required');
        // Remove the injected asterisk
        $field.find('.lf-required-asterisk').remove();
    }
}

/********************************************************************************
 * RULE: JIT Message / Silver Automated Meter Readings Requested
 * Shows and makes required fields #q487 and #q488 when:
 *   - At least one Order Detail checkbox is selected (Hardware, Production,
 *     Maintenance Services, or MPS)
 *   AND one of the following is true:
 *     a) Customer is NOT new AND customer type is "Silver"
 *     b) Customer IS new AND signed MRR value is less than 500
 * Otherwise, hides the fields and removes their required state.
 ********************************************************************************/
function checkJitMessageAndSilverAutomatedMeterReadingRequested() {
    // Read current field values
    const isNewCustomer    = $('input[name="Field5"]:checked').val();
    const customerType     = $('#Field395').val();
    const signedMrValue    = parseFloat($('#Field358').val()) || 0;

    // Order Details checkboxes
    const isOrderDetailsHardware   = $('#Field15-0').is(':checked');
    const isOrderDetailsProduction = $('#Field15-1').is(':checked');
    const isOrderDetailsMaintServ  = $('#Field15-4').is(':checked');
    const isOrderDetailsMPS        = $('#Field15-5').is(':checked');

    // Determine visibility / required state
    const shouldShow =
        (isOrderDetailsHardware || isOrderDetailsProduction ||
         isOrderDetailsMaintServ || isOrderDetailsMPS) &&
        (
            (isNewCustomer === 'No'  && customerType === 'Silver') ||
            (isNewCustomer === 'Yes' && signedMrValue < 500)
        );

    if (shouldShow) {
        // Show fields first, then mark as required (so inputs are detectable)
        $('#q487, #q488').show();
        setRequired($('#q487'), true);
        setRequired($('#q488'), true);
    } else {
        // Remove required state first, then hide
        setRequired($('#q487'), false);
        setRequired($('#q488'), false);
        $('#q487, #q488').hide();
    }
}

/********************************************************************************
 * INIT: Run rule on page load and re-run on any relevant field change
 ********************************************************************************/
$(document).ready(function () {
    // Initial evaluation
    checkJitMessageAndSilverAutomatedMeterReadingRequested();

    // Re-evaluate when any controlling field changes
    $('#Field395, #Field358, #Field15-0, #Field15-1, #Field15-4, #Field15-5')
        .on('change', checkJitMessageAndSilverAutomatedMeterReadingRequested);

    $('input[name="Field5"]')
        .on('change', checkJitMessageAndSilverAutomatedMeterReadingsRequested);
});