We filled out the app and were approved. Tried to login and it doesn't recognize us. "Kicked whilst connecting to lobby. Sandlot is white-listed, apply..."
Are you sure you got the approved email?, you get one when you join the fourms as well as when you are added to the whitelist.
You should be able to enter The Sandlot now. I think @Kayah57 is correct. Comparing the time stamp for your post here and the timestamp for your whitelist app, your application had not yet been approved. If you have further issues logging onto the server, please respond to this post.