Behavioral Question in Interview

I just did a screening call and encountered a question that cornered me. He gave a situation in that a client required to have a meeting with 4 MDs in four locations (like SF London HK...) at 9 AM, but he just sent this request to me at 8:20 AM... I said I'll email them first but it is hard to gather 4 of them because of the time zone. If some of them cannot make it, two options: invite more MDs in the same locations, or invite VPs who worked in the same group and are familiar with the work to the meeting if they were awake. 

I answered it like it is really hard to gather 4 from 4 locations, just invite more MDs in one same location... And he then came up with a follow-up question: "But the client still needs people in 4 locations, what will you do?"

How would you answer this question and what will you do in that situation?