Cookie Code breaks site – Set your own Cookie based on a (custom) Consent Categ

Hello
I am following your guide here https://complianz.io/set-your-own-cookie-based-on-a-custom-consent-category/

I created a .php called cloudflare-consent.php and uploaded it to the MU Plugins folder
but when I add the second part “Adding a custom cookie”
that code breaks the site

function cmplz_set_rlx() {
	ob_start();
	?>
    <script>
        function cmplz_set_rlx_cookie(value){
            let secure = ";secure";
            let date = new Date();
            let name = 'rlx-consent';
            date.setTime(date.getTime() + (complianz.cookie_expiry * 24 * 60 * 60 * 1000));
            let expires = ";expires=" + date.toGMTString();
            console.log("set cookie with string "+name + "=" + value + ";SameSite=Lax" + secure + expires);
            document.cookie = name + "=" + value + ";SameSite=Lax" + secure + expires;
        }

        /**
         * Set a complianz rlx cookie and the custom cookie on save preferences
         */
        document.addEventListener('click', e => {
            if (e.target.closest('.cmplz-save-preferences')) {
                let rlx_enabled = document.querySelector('input.cmplz-functional').checked;
                if (rlx_enabled) {
                    console.log("save prefs, rlx enabled");
                    cmplz_set_cookie('rlx', 'allow');
                    cmplz_set_rlx_cookie(true);
                } else {
                    console.log("save prefs, rlx disabled");
                    cmplz_set_rlx_cookie(false);
                    cmplz_set_cookie('rlx', 'deny');
                }
            }
        });

        document.addEventListener("cmplz_fire_categories", function (e) {
            var consentedCategories = e.detail.categories;
            if ( cmplz_in_array( 'marketing', consentedCategories ) ) {
                cmplz_set_cookie('rlx', 'allow');
            }
            if ( cmplz_in_array( 'rlx', consentedCategories ) ) {
                cmplz_set_cookie('rlx', 'allow');
            }
        });

        document.addEventListener("cmplz_before_cookiebanner", function(e) {
            if ( cmplz_get_cookie('rlx') === 'allow'){
                console.log("set checkbox rlx to true");
                document.querySelector('input.cmplz-functional').checked = true;
                _satellite.setVar("Analyticsconsent","true");
                _satellite.track("PageView");
            } else {
                _satellite.setVar("Analyticsconsent","false");
                //set a default false value, as workaround for rlx issue which checks for false cookie, instead of also checking for not-existing one.
                cmplz_set_rlx_cookie(false);
            }
        });

        /**
         * Handle revoke
         */
        document.addEventListener("cmplz_revoke", function(e) {
            console.log("revoke rlx cookie");
            cmplz_set_cookie('rlx', 'deny');
            cmplz_set_rlx_cookie(false);
        });
    </script>
	<?php
	$script = ob_get_clean();
	$script = str_replace(array('<script>', '</script>'), '', $script);
	wp_add_inline_script( 'cmplz-cookiebanner', $script );
}
add_action( 'wp_enqueue_scripts', 'cmplz_set_rlx',PHP_INT_MAX );

I added the code in a code snippets plugin first and it would not activate because of an error, so then I thought I must add it to the bottom of the mu plugin I created, but that breaks the site.

Please assist thanks