Questions about redirection URL for apps installed from Intercom App Store.

Hi team, I was wondering if the documentation on redirection here is up to date? Here are the videos my team made on this topic.

pt1. https://www.loom.com/share/0b4c6afc4e594be4b93081882ba2b9ea

pt2. https://www.loom.com/share/e730ddd7dcf34c1fa163c191e15af4bb

Based on the documentation it said that we should use https://app.intercom.com/appstore/redirect?install_success=true and https://app.intercom.com/appstore/redirect?error_message=<your error message> for the successful and failed installation respectively. But from our testing, those 2 URLs will redirect our users back to Intercom's inbox page not our App modal on the App Store, and there's no error nor success message on either case.

We, however, found out that if we use the following URL which isn't documented https://app.intercom.com/a/apps/g9guvxdz/appstore?app_package_code=simplesat-qhib&error_message=<error message here>&install_success=false it does work and bring users to our app modal open on the App Store correctly and also show the success message.

So, I have 3 questions

1. I'm about to submit the app for review, what should be the URL I used to the app in review, should I follow Intercom's documentation and lose redirecting users back to our app modal on the App store, or should we use this undocumented redirect URL. I'm not sure if this will have any implication in the review process
2. Do I have to record the video for App approval again including installing the app from the App store? If so how do I test install our app from the app store because we also need to wait for you guys to approve our app settings. Or can we use the previous video that we submitted? The only problem with our last submission is that we didn't configure our app to install from Intercom App Store because we utilize Canvas capability.
3. About the app package code, simplesat-qhib, does the part afther the hyphen also considered the package code, or to rephrase that, does this app package code ever changed when we submit a new app version e.g. Change permission and stuff.

Thank you in advance,