Getting tiles in Motion Vector (Movie Queue)

Im rendering a 4k sequence in Unreal 5, I need to use the High Resolution setting so my GPU doest crash, but when I do it, the Motion Vector pass has tiles on it, so I cant use it to generate motion blur in NUKE

someone knows what is happening here? thanks

Update on this, Using PATH TRACING I don´t need to use the High Resolution feature, I can render in 4K without the computer crashing. Disabling HR is giving me the Right motion vector pass