From episode one we see how Mike is spying on Carrie ,following her sms/calls closely … So Q is how has she been contacting (texting/calling) Yevgeny so privately – without CIA knowing it ? She did so in the last episode , even after she talked to Saul , as a result he picked her up at the airport

My guess is with all the other stuff happening it fell off his radar. And once he talked to Saul, who said he’d handle it, he figured it was a done deal.

I’m not sure if Carrie has been texting with Yevgeny the whole time though (just showing up at his place in the night). Maybe just in this episode.