@JRSettles
I had no problems with mine and swithing to an older WPA is not likely the issue as your garage door opener is new enough that it shuould support WPA2. Is the problem that the garage door opener cannot connect to your network?
The app is used to configure that connection initially. Opening port 8883 would only be an issue once the garage door opener was connected to your Wifi as that is the port it communicates on to MyQ servers. Please clarify if the problem is with the app or connectiong your garage door opener to your router using the app.
When your garage door opener is not connected to a wifi network, it falls into an AP mode where you are supposed to connect your phone to its Wifi SSID. The app may broker this connection or direct you to connect manually. Either way, the app will then have you select the wifi network and passphrase of your router that the garage door opener should connect to. If you have gotten this far and the garage door opener is on your network, then port 8883 would be the next step.
I think you have to create a MyQ account as well before all this if memory serves me correctly.