Those guesses are as good as any - it is not easy to make out what is being said on a few of those words.
However, the title of the song gives an all important clue. It is "Mr. Sneaky" right? Because of that, I always thought that the last two words were "Monsieur Cannaille" which is a translation of Mr. Sneaky.
One thing to remember about Keith is that he is kinda faking it when it comes to French. I am glad that he tries, but you can tell it doesn't come to him naturally. I am not saying that I am a renowned Cajun and Creole language expert, or that I could do any better than Keith, but I know enough to be able to tell the difference someone who really knows, and someone who (like me) is coming to it after the fact.
I learned Mr. Sneaky a long time ago, and found out later about a very similar sounding song by Beau Jocque. Many of us have heard about the bad blood between those two, and charges of one of them stealing the others songs and licks. On the basis of that, I always thought that Keith was referring to Beau Jocque as Mr. Sneaky. What was that other Keith Frank song in which he is talking about "the pork chop's not hot" and "the pork shop's not s***" (with pork chop being some kind of nickname for Beau Jocque)?
The song you're referring to is "One Shot" by Keith. The lyrics imply "One shot from my Get On Boy" was far better than the rival "Cornbread" tune at the time, in which Beau makes the piece of porkchop reference. The Cornbread song as many may have heard, was invented by Willis Prudhomme. Not sure if Willis ever recorded it, but rumor has it Beau stole it (or re-did it) from Willis.
I also think Keith's tunes, "You've Been Watching Me" and "Let Them Talk" were directed at Beau.
Must be nice to get Keith's attention enough for him to feel threatened enough to refer to ya in a tune!
And then there's J. Paul's tune on his "Taking Over" CD, "The Story" which is a total dys on Keith... "...one monkey from the East; don't run no show..." amongst other lyrics. Ever notice J. Paul and Keith don't play on the same billing -- ever?
BTW, Mr. Sneaky is really the same tune as Keith's "Now Is The Time." Just with different lyrics and a more staccato groove.
I only ever had one conversation with Mr. Willis, but in that conversation he talked about having given the Cornbread song to his friend Beau Jocque. So I think it was a friendly transaction.