Using custom road network in OSRM map matching request

For a project I'm using OSRM to map match a series of GPS measurements to a custom road network. My goal is to provide insight in where but more importantly how many times the vehicle has visited each road segment in the road network. My desired output is (1) an attribute table of the road network with an extra column that shows the number of times the vehicle drove through the street, (2) a map visualisation of the flow of traffic through the network, with the width of each line segment representing the amount of traffic (i.e. based on the visit frequency values in the attribute table). Something like this:

I have been able to convert a custom road network in shapefile format to .osm data using ogr2osm and succesfully map match the GPS points to this network. Using the option "annotations=nodes" in the OSRM request I'm able to get all the node id pairs and geometry from the API response. This would allow me to tabulate and rank the most common segments, and display them visually, no joining to a PBF required. However, the original node id's from the shapefile appear to have lost after the conversion. Instead, new node id's have been chronologically numbered in the .osm file (see below). This makes it impossible to come to the desired output as described above. Does anyone have a solution to retain the original node id's from the original shapefile road network? Or does somebody havee a better solution for what I'm trying to achieve?