Will there be an update for the TRTH library for R? As for now, none of the other solutions seem to be working...
Currently, there is Tick History V2 which supports REST API. The data is from DSS server. I think that you can use R to request data from this REST API.
For more information, please refer to Tick History 10.8 REST API User Guide at https://developers.thomsonreuters.com/thomson-reuters-tick-history-trth/thomson-reuters-tick-history-trth-rest-api/docs