Rimuru has returned to Jura after having attended Walpurgis. Diablo informs Rimuru of his mission to deal with the Kingdom of Falmuth. Having presented the kingdom with three options at a resolution, the clock on the week for their answer ticks down.
So he's the third party that 
the nobles will force the responsibility on.
إذاً هو الطّرف الثّالث الّذي سوف
يفرض النُّبلاء المسؤوليّة عليه
Ah, so wird er für die Adeligen zu der dritten
Partei, der die Schuld gegeben werden kann.
C’est donc lui
qui sera rendu responsable de ce fiasco.
Diventerà la famosa terza parte a cui i nobili
cercheranno di affibbiare la responsabilità.
Então ele é o "terceiro" a quem os
nobres vão impor a responsabilidade.
В общем, он и станет тем самым
козлом отпущения.