What kind of logs do You want? Yes I can do debug because the machine is used only a little.
Maybe the check_connection function is good for first time after mount or only after clicking "Summary" and there should be new function for example like check_mount_cifs whitch would not use smbclient but should do check in local mount place (it would be much more faster because making new connection, login again and all the things whitch are done there like negotiating protocole version and authentication type is not required). It's also much more clean for logs on destination CIFS server.
What do you think about my idea?