I disabled a mailbox and realized I needed to grab some more emails out of it. I looked in the disconnected mailboxes section but didn’t see it. There is no command that I know of to do a force clean up like there was in Exchange 2003 GUI but here is the command from Exchange Management Shell.
Clean specific mailbox storage group:
Clean-MailboxDatabase "Mailbox Database"
Clean all mailbox storage groups on server:
Get-MailboxDatabase | Clean-MailboxDatabase
Then I refreshed the Disconnected Mailbox section and the user was there.