Edge blur breaking down in Movie Render

Text typically uses a distance field generated texture to make the edges look good. I have read that people have been having troubles with this, so my suggestion would be to try to put the text into a widget, then spawn the widget in the world as a 3D object. Found some info about it here: How do I put a custom font in a TextRender? - #2 by EnricoUniverse

Otherwise have a look here: