When you import your list, you should do a progression change on that list to change the status of the members of that program to attended.
Unless you auto assocaite a campaign with a program, leads will not push to the campaign this way. The progression status change mentioned above should help address your status issue if you do assocaite programs and campaigns. Just make sure they are sharing the same exact statuses. (i could be a bit off here try it out, i use workflow campaign pushes)
If you don't assocaite a campaign and a program, you must do a manual add to campaign flow and in this flow it gives you the option to select the status.
Make sure your campaign statuses match in salesforce and marketo. If not, this could be your issue, seems you have things set up ok.