AWS Cost Explorer Tags Not Showing All CloudFormation Stacks

Regarding Tags, in order for Tags to show up in the billing system, including Cost Explorer, those tags need to be allocated for costs [1]. This is a process where you select the tags to show up in billing data and from then on (not retroactive), they will show up.

Regarding the Application Manager, my widget states that it is based on Cost Allocation Tags as well, and even has a recommendation of which tags to enable for cost. It further states it can take up to 24 hours for the data to show up in Cost Explorer and the Cost Explorer Widget.

[1] https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/cost-alloc-tags.html