Ok guys, I've solved it! It was some godforsaken problem with my .p12 file.

1. Tried creating a .p12 file by exporting both the private key and the cert. FAILED.
2. Tried creating a .p12 file by exporting just the private key. FAILED.
3. Tried creating a .p12 file by exporting just the cert. SUCCESS.

So, notifications are now working for me. Not sure how to mark this question as solved, but it's solved. Thanks for all your help!

@Paul-Winterhalder Yes, I do have other devices I could try. I realize this probably isn't a brainCloud problem, so I appreciate all the help you guys have given me, here. Thank you, and I'll keep trying to figure it out.

@Steve-Jones Yes to both. My cert is for distribution and my app entitlement is set to "production". No, the notification from pushtry.com never appeared on my device, despite the service claiming to have been successful.

@Paul-Winterhalder

#1 - My app was not running at the time, and I tried again.
#2 - That's correct. And I'm still getting the same INVALID_TOKEN error in "Recent Errors".

My app does have the correct "production" entitlement, yes.

@Paul-Winterhalder I exported just the private key without the cert and pushtry.com now says, "Push notification sent successfully". So, I uploaded this new .p12 file to brainCloud. However, I never actually received a notification on my device, and am still unable to send notifications via the brainCloud dashboard.

@Paul-Winterhalder That gives me something to pursue. Thanks, Paul!

@Paul-Winterhalder That's what I thought at first, but no, my password is correct.

@Paul-Winterhalder I'm getting "The credentials supplied to the package were not recognized." No clue what that means, unfortunately.

@Paul-Winterhalder Thanks, Paul.

I'm getting an INVALID_TOKEN error when calling scheduleNormalizedPushNotificationMinutes() from cloud code. The "Send Notification" button in the BrainCloud dashboard also fails to work.

1. I've correctly uploaded/configured my .p12 file etc.
2. I'm correctly retrieving the device token from the client, and it shows up on the BrainCloud dashboard.
3. My Apple certs/profiles etc. are in order.

                var alertContentJson = {
                    "body": "content of message",
                    "title": "message title"
                };
                var customDataJson = {
                    "field1": "value1",
                    "field2": "value2"
                };
                var minutesFromNow = 1;
                var otherPlayerId = "someId";
                var pushNotificationProxy = bridge.getPushNotificationServiceProxy();
                
                var postResult = pushNotificationProxy.scheduleNormalizedPushNotificationMinutes(otherPlayerId, alertContentJson, customDataJson, minutesFromNow);