Wordpress Background Revolution Slider Breaking on Upgrade

I'm new here and hoping for a bit of help. I’m working on a wordpress custom theme that was build over 8 years ago which has a Slider Revolution slideshow sitting in the back of the home page being called out from the footer area and alternative background images when not the home page. The problem is that I can no longer edit the slides on the original Revolution Slider 4.1 as it was so old, so upgraded to the latest version, but the slide then completely disappeared from the home page and only shows a black background.

I have been in touch with Theme Punch, but they have said debugging custom themes is beyond their support. I wonder if anyone has come across any similar issues and have any solutions?

Website with old version of revolution slider is https://hmdopticians.co.uk Testing on https://zincdesigns.co.uk/hmd with the latest version of slider revolution.

Here is the php in the footer:

<?php if (is_front_page() == true) {   
                //This is where the parallax will need to go  
                putRevSlider("home-slider") ;
                ?>

                <script>
                    (function($){
                        $(document).ready(function() {
                            $(window).resize(function() {
                                var windowWidth = $(window).width();
                                $('.forcefullwidth_wrapper_tp_banner').css({'width':windowWidth + 'px'});
                            });
                        });
                    })(jQuery);
                </script>

            <?php
            } else { 
                $min=1;
                $max=3;
                $num = rand($min,$max);
                
                switch($num){
                    case 1:
                        echo '<div id="static_background1"></div>';
                        break;
                    case 2:
                        echo '<div id="static_background2"></div>';
                        break;
                    case 3:
                        echo '<div id="static_background3"></div>';
                        break;                    
                }
            } ?>

Here is the CSS relating to .forcefullwidth_wrapper_tp_banner:

.forcefullwidth_wrapper_tp_banner{
z-index:0;
position: fixed !important; 
top: 0px; 
right: 0px; 
left: 0px; 
width:inherit !important;
padding:0px; 
margin:0px; 
/* Preserve aspet ratio */
-webkit-background-size: cover;
-moz-background-size: cover;
-o-background-size: cover;
background-size: cover;
overflow: hidden;}