Yes if multiple users are signed into the device, package and task sequence deployments may not appear in Software Center. Sometimes, restarting the device or moving the device out of the current collection and then adding it to the collection again will have different results.
You can also monitor the deployment status of your task sequence in the Monitoring/Deployments of Configuration Manager console.
In addition, starting in version 1906, the task sequence debugger is a new troubleshooting tool. You deploy a task sequence in debug mode to a small collection. It lets you step through the task sequence in a controlled manner to aid troubleshooting and investigation.
As for how to deploy complex applications using task sequences, I hope the following information is helpful to you. Starting in version 2002, you can install complex applications using task sequences via the application model. Add a task sequence deployment type to an app either to install or uninstall the app. What needs our attention is:
You can only add a non-OS deployment task sequence as a deployment type on an app. High-impact, OS deployment, or OS upgrade task sequences aren't supported.
Make sure your user account have permission to read task sequences.
Don't use the Install Application step in this task sequence. Use the Install Package step to install apps.
You can't yet deploy an app task sequence to a user collection
The task sequence deployment type is a pre-release feature, so you need to enable it first.
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