Well I don't know what to think really. My initial belief was that he indeed spoke with Outosideo and the Doc only forwarded the call through his phone somehow, even though the former surely has to know Akira's number himself.
I was led to believe it because, Outside's voice was a bit different than the doctor's, and how we didn't heard the Doc speaking in the same room, plus if I think about it it's unreasonable to assume the Doctor managed to record the first call explaining the rules. I reckon the Doc doesn't have enough to time to quickly run/sprint in (?) between the time we hear "I eagerly pray that you continue being a messiah" and the time Akira addresses him after the call ended. (and there's simply no real reason to confuse us viewers with that, anyway).
Of course that has many flaws as I mentioned few posts above (I seriosly doubt he can contact Outosideo in the first place), but playing a recording seems a bit unbelievable too. It might be just me though.
By the way, I'm quite certain there must be some reason why they showed us the Doctor's family picture. On another note, am I the only one who thinks, they look the same? (except the hairstyle of course)
