Customers Pending Approval will show in both the "All" and "Pending Approval" tabs.
Customer Pending Approval in the All Tab
Customers pending approval can be approved from any tab by clicking the gear icon and selecting "Approve Customer"
Approve via Row Actions
Customers can also be approved in bulk by selecting the pending approval customers and choosing "Approve Selected Customers" from the Bulk Actions list.
Approve via Bulk Actions