Munich to Salzburg train number differs in rail planner and DB app

Hello, 

I am planning a trip from Munich to Salzburg. 
 

I noticed through the DB app/website the train number is RJX 65 while in the rail planner app it’s EC 65. Both depart and arrive at exactly the same time (11:11 to 13:06) and from the same station. 
 

Are they the same train? Can I add the EC 65 ticket to my eurail pass and book a seat from the DB website for the RJX 65? If not, why can I not see the RJX 65 train on the rail planner app and also cannot see the EC 65 train on the DB website? 
 

can someone please help clarify this?