I believe it is not a simple_oc error (checked the quoting and it seems ok). If the password contains an @ or /, then I don't know how this can be encoded in an url. You can check if your problem is due to owncloudcmd by directly calling it

Where the location may or may not contain remote.php/webdav (both should work).

I once had a similar problem which is fixed in the current owncloudcmd: owncloudcmd seems to parse the input URL several times. My guess: one of the parsings is buggy, probably for storing the sync result in a database file. Since this fails, he undoes the sync but leaves the directories.

The whole "username@password in url" is ugly and will probably be fixed by me in the next version.