Derek doesn't sound super pissed about having to answer the phone, so Newt takes this as a good sign.

"Heyyyyyyy, it's your old buddy, Newt! Listen, guy, you busy? I need a favor, not even a huge one, I'm just kind of lost in the woods and fear that I will be mauled or something, so y'know. I could use a hand." Newt crosses his fingers because please, this is a little embarrassing but it's not like he really has a choice right now.