I would like to prevent to download from Quick look UI in AR for iOS

I would like to develop an application with AR.
That AR model contains a secret data, so I would like to prevent to download.

My app’s flow is following.
Firstly, I create usdz data through Playcanvas.

CreateExportUsdz.prototype.exportUsdz = function(){
    const _entity = this.app.root.findByTag("AR")
    const _option = {
        maxTextureSize: 1024
    }

    // 
    const _usdzExporter = new pc.UsdzExporter()
    _usdzExporter.build(_entity[0], _option).then((arrayBuffer) =>{
        const _blob = new Blob([arrayBuffer], {type: "model/vnd.usdz+zip",})
        const _url = URL.createObjectURL(_blob)

        const a = document.createElement("a");
        a.setAttribute("rel", "ar");
        a.setAttribute("href", _url);
        a.style.display = "none";
        document.body.appendChild(a)

        a.click();
        a.remove();
        setTimeout(() => URL.revokeObjectURL(_url), 10000);

    }).catch(console.error)
}

Secondly, I convert it BLOB format.

Lastly, I pass it to Html.

AR view is succeeded.
Unfortunately, we could download from red marked UI. (Save as File)

I would like to prevent it.
If someone has answer, could you tell me it?