Leaving LA was not something Eren was willing to do. Not before that event took place. That's why he didn't take much time before politely refusing Jason's offer:
"The offer is indeed tempting, Jason. I can't speak for Renita, but I'll have to decline. We all know Royal Ren is not a nice place for commoners like me.
Maybe things would work out for you and our friend Ivor here. I can now see why he sticks close to you. You are his ticket to enter the place he couldn't go because of his brother's death."
Eren looked at Ivor and said this in a plain voice. He remembered Ivor's long-winded speech about how he was unable to go to Royal Ren because of Isaac's death. With Jason's support, Eren didn't think the guy would have to worry about excessive non-disclosure contracts. His succession to Isen's position also won't be hampered.
Ivor wanted to rebuke Eren but he couldn't. This was exactly why he was mindful around Jason.
"I'll always… *cough... I mean I'll also stay with Eren."
