How to access clusterProperties of a clustered vector source created using supertiler library?

I am converting a GeoJson of 10 million points to MapBox tiles (.mbtiles) using the supertiler library.

var vList = ['a', 'b', 'c', 'd', 'e', 'f', 'g']; // List of video IDs
supertiler({
    input: '../file.json',
    output: '../file.mbtiles',
    maxZoom: 12,
    initial: () => {
        var t = Object();
        videoList.forEach(v => {
            t[v] = 0
        });
        return t;
    },
    map: (props) => {
        var t = Object();
        videoList.forEach(v => {
            t[v] = v === props.i ? 1 : 0; // i is the video ID - property of a single point
        });
        return t;
    },
    reduce: (accumulated, props) => {

        videoList.forEach(v => {
            accumulated[v] = accumulated[v] + props[v];
        });

    }
}).then(null, (err) => console.log(err));

I am then uploading the .mbtiles files to the Mapbox using their Uploads API so that I can add the data to my application as a vector source.

map.addSource(layerID, {
    type: 'vector',
    url: 'mapbox://octopusmapbox.vLayer',
});

map.addLayer({
    id: `${layerID}-cluster`,
    type: 'circle',
    source: layerID,
    'source-layer': 'geojsonLayer',
    maxzoom: 12.99,
    paint: {
        'circle-color': 'hsla(1, 86%, 65%, 0.5)',
        'circle-radius': [
            'interpolate',
            ['linear'],
            ['get', 'point_count'],
            0,
            20,
            156342,
            200,
        ],
        'circle-opacity': 0.7,
        'circle-stroke-color': '#f35e5b',
        'circle-stroke-width': 1,
    },
});

When I console log the properties of the cluster, I do not see any cluster properties, but only the following:

{
  "cluster": true,
  "cluster_id": 612,
  "point_count": 1399,
  "point_count_abbreviated": "1.4k"
}

How do I access the properties 'a', 'b', 'c', etc.?

The end goal is to achieve something like this.

Thanks in advance.

The vector layers take time to propagate the changes to the source when used in the application. My code is generating the clusterProperties correctly.