Adding axis markers to FastLineRenderableSeries

I’m trying to add a axis label/marker to the yAxis of my chart.
This label should follow the intersection between a FastLineRenderableSeries (that i’m using to render a moving average filtered dataSeries) and the yAxis.

I tried to extend the “draw” method of the FastLineRenderableSeries to draw a label ontop of the yAXis, using the “drawModifiersAxisLabel” helper function. Like:

class CustomFastLineRenderableSeries extends FastLineRenderableSeries {
draw(renderContext: WebGlRenderContext2D, renderPassData: RenderPassData) {
    super.draw(renderContext, renderPassData)
    const yAxis = getYAxis(this.parentSurface);
    drawModifiersAxisLabel(
        yAxis,
        renderContext,
        150, // testing values
        "#00ff00", // testing values
        "#00ff00", // testing values
    );
}

but the label don’t get drawn.

The attached image shows the desired feature (image from another charting lib)

How can I implement this?