can't find time machine restored mailbox
I changed one of my imap gmail accounts to a group account and create myself a new one to receive forwards from group. I went to mail settings and changed the settings of the account and now i realized that actualy I deleted the old one (with over 1000 mails) and setup a new one. I went to time machine, found the old account and restored it. I find the email on the search but can't find where they are. I can see they are in INBOX-3. I would like to upload all these old mails to the account/server. I could even manage to copy the folder com.apple.Mail.Backup.mbox where the INBOX folders are to my desktop but still can't import them to my new account. How do I do it ?
MacBook Air, OS X Mountain Lion (10.8.5)