Inaccurate Google Maps Elevation Service response when splitting a too large path

Question

This is a bit of a question with some level of detail to it, so let me first explain the situation, then my implementation and last the question so you understand best.

Answer 1

The last remaining issue has also been solved with the help of this SO question: How to re-run a javascript promise when failed?. So if jfriend00 replies to this question I can award the bounty to him, since that's the trick that helped me out in the end.

To be sure the function resolves at status OK, retries at OVER_QUERY_LIMIT and reject at any other status I had to put the Promise logic within a function and call that function, like so:

function getRouteElevationChartDataBatchPromise(batch, batchSize) {
    return new Promise(function(resolve, reject) {
        function run(batch, batchSize) {
            var elevator = new google.maps.ElevationService();
            var thisBatchPath = [];

            for (var j = batch * batchSize; j < batch * batchSize + batchSize; j++) {
                if (j < directions.routes[0].overview_path.length) {
                    thisBatchPath.push(directions.routes[0].overview_path[j]);
                } else {
                    break;
                }
            }

            elevator.getElevationAlongPath({
                path: thisBatchPath,
                samples: 512
            }, function (elevations, status) {
                if(status == google.maps.ElevationStatus.OK) {
                    routeElevations = routeElevations.concat(elevations);
                    resolve();
                } else if (status == google.maps.ElevationStatus.OVER_QUERY_LIMIT) {                        
                    setTimeout(function () {
                        run(batch, batchSize);
                    }, 200);
                } else {
                    reject(status);
                }
            });
        }

        run(batch, batchSize);
    });
}