As mentioned in the other query, RFA is a content agnostic API used to consume realtime data from a server.
When you consume realtime data using RFA, in theory, you can expect to get the same data at the same tick rate and timeliness as Eikon. However, there could be some variances e.g.
Quite often an organisation publishes realtime data internally on multiple services with conflation and/or delays - in addition to the full tick non-delayed service.
This is again something that you would need to confirm with your Market Data - to check if the Eikon is conflated and if the TREP service which you are consuming using RFA is conflated or not.