Google Maps API MarkerClusterer.js error, “Cannot read type of undefined (reading ‘maxZoom’)”, error is within library code. How can I resolve this?

I’m having an issue with the Google Maps Javascript API where it fails to zoom in on a point because it is passing back the error in the title. I checked previous questions, and they say that this is an issue with using a deprecated version of the MarkerClusterer.js, but it was working fine until yesterday at the latest.

The function in question that’s throwing the error is below, the specific line is noted by comment.

google.maps.event.addListener(this.map_, 'zoom_changed', function() {
    // Determines map type and prevent illegal zoom levels
    var zoom = that.map_.getZoom();
    var minZoom = that.map_.minZoom || 0;
    var maxZoom = Math.min(that.map_.maxZoom || 100,
                         that.map_.mapTypes[that.map_.getMapTypeId()].maxZoom);  //HERE
    zoom = Math.min(Math.max(zoom,minZoom),maxZoom);

    if (that.prevZoom_ != zoom) {
      that.prevZoom_ = zoom;
      that.resetViewport();
    }
  });

Naturally, this means that that.map_.mapTypes[that.map_.getMapTypeId()] is returning undefined, but no idea what to do about that.

I access the library by link, which is below. Is there a way to acquire the version that was up and running a few days ago, since that version wasn’t failing (as far as we know)?

<script src="https://developers.google.com/maps/documentation/javascript/examples/markerclusterer/markerclusterer.js"></script>

I have tried other links to different versions, including the rawgit that was linked in this thread. I have also tried manually definiing maxZoom in the options as has been suggested by other threads, but none of the suggestions have solved the problem.

            var mcOptions = {
                
                styles: clusterStyles,
                maxZoom: 15
                
            };

            markerCluster = new MarkerClusterer(map, markers,mcOptions);