leaftime | Leaflet.timeline for R leaflet | Map library

Below is example code taken from the examples given in the documentation for the R leaftime package. It creates a map with a timeline that shows the points appearing over time. I would like labels to be added to the points to show the id number of each point. By looking at the code, I assume the JS function in the code is actually passing JavaScript to leaflet to customise the map. I understand from here https://gis.stackexchange.com/questions/245621/how-to-label-geojson-points-in-leaflet that I need to add in the tooltip function but have been unable to modify the below R code to achieve the desired result. I would be grateful for any assistance.