How to use BlueSocket to send UDP Datagrams?

Question

I cannot see any UDP-related network activity via Wireshark when executing the following code (hardcoded/shortened for simplicity). Using Swift 4, running simulation on iOS 11 iPad Pro.

let addr = "192.168.0.18"
let port: Int32 = 1900
let fullAddr = Socket.createAddress(for: addr, on: port)

try socket = Socket.create(family: .inet, type: .datagram, proto: .udp)

try socket?.write(from: "Hello!", to: fullAddr!)

The goal is to send MSEARCH for device discovery. I was successful in sending datagrams using SwiftSocket with the same information, and even got a reply from the device I'm attempting to communicate with (Sony A7RII). I verified this with Wireshark. Unfortunately I had to switch to BlueSocket because it is much more complete. Now I can't see any network activity.

I feel like I'm missing something obvious, but cannot see what it is.

First time Swift developer, also a networking beginner. And first SO question. Wow!