Photoshop UXP - Timeline and Frames Access

I have the following Code that works fine in an old style .jsx file:

function getFrameCount() {
    var r = new ActionReference();
    r.putProperty(charIDToTypeID('Prpr'), stringIDToTypeID('frameCount'));
    r.putClass(stringIDToTypeID('animationClass'));
    var ret = executeActionGet(r);
    return ret.getInteger(stringIDToTypeID('frameCount'));
}

I've been attempting all day to either do this natively within UXP or to figure out how to call a working .jsx script from a button in my UXP plugin.  

I can't find a way to get timeline queries working in UXP and would love some guidance