I may have entirely misread your original post and thought that you meant you *could* connect, but it required a password (which would make sense ;p), not that the whole thing just plain didn't work ^^.
The latter would just imply you're doing something wrong in the NM chain.
My usual answer for that is: just write a wrapper shell script and launch that, that'll be quicker than trying to debug a typo/thinko

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