That's right! Murata is still a threat on GGG's career even though there's a much more anticipated fight ahead of him which is the trilogy, even so he still needs to face Murata first and defeat him in-order to retain the hype of the fight that he is been calling for years now.
About Murata, I know that he is been really preparing for this fight because these are the fights that he has probably waited for years to have that one fight that will change his career and defeating GGG will be a good stepping stone for his career as it would really give him more opportunities in this industry.
What interests me on this fight is not how Murata will perform or his motivation but how GGG will handle himself going to this fight and the fight day, old age is catching up with him although I have not seen him slowing down on his last fight, every boxer's dilemma is their age and the body's reaction, the mind is still there but the body does not react to what the mind wants, it's not on Murata but if GGG still has it, if he still has it GGG can win this easily.