Explanation
To capture and categorize email Not Sent events and insert them into a data extension using Automation Studio, Northern Trail Outfitters should use the following order of activities:
Data Extract with the Tracking Extract type. This activity will extract tracking data, such as Not Sent events, from Marketing Cloud and place a zipped file in the Safehouse.
File Transfer from Safehouse. This activity will move the zipped file from the Safehouse to an Enhanced FTP location.
File Transfer unzip. This activity will unzip the file and place it in an Enhanced FTP location.
Import File. This activity will import the file into a data extension.
Data Extension Extract is not a valid extract type for tracking data. SQL Query is not an activity that can insert data into a data extension from a file. Data Factory Utility is not a valid activity in Automation Studio.
References: https://help.salesforce.com/s/articleView?id=sf.mc_as_data_extract_activity.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.mc_as_file_transfer_activity.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.mc_as_import_file_activity.htm&type=5

Explanation
The reason why the Journey does not inject customers when their order status is updated is that orders are not being updated from not meeting criteria to meeting criteria. A Salesforce Data Entry Source only injects records into a journey when they change from not meeting the entry criteria to meeting the entry criteria. For example, if the entry criteria is order status equals New, then only orders that change from a different status to New will be injected into the journey. Orders that are created with a status of New or change from New to another status will not be injected into the journey. References:
https://help.salesforce.com/s/articleView?id=sf.mc_jb_salesforce_data_event.htm&type=5

Explanation
To export a data file to its SFTP containing all subscribers who did not receive their intended email in the last
24 hours, Northern Trail Outfitters should use a Data Extract Activity in their automation. A Data Extract Activity is an activity that allows marketers to extract data from Marketing Cloud and place it in a file on an Enhanced FTP location or an external SFTP location. The Data Extract Activity can use different extract types, such as Tracking Extract or Data Extension Extract, to export different types of data. References:
https://help.salesforce.com/s/articleView?id=sf.mc_as_data_extract_activity.htm&type=5

Explanation
To make sure the decision splits reflect the correct tent for each customer, Northern Trail Outfitters should use Entry Data as the type of data in the decision splits. Entry Data is the data that is captured at the time of entry into a journey and remains static throughout the journey. Entry Data can include data from data extensions, Salesforce objects, or API events. Using Entry Data will ensure that the decision splits are based on the tent that each customer bought at the time of entry, and not affected by any subsequent purchases or data changes.
References: https://help.salesforce.com/s/articleView?id=sf.mc_jb_entry_data.htm&type=5