I'm not sure why this is called a rebus, since there are no things (or pictures of things) involved, but it is a sort of disguised writing (not quite a code, since there is no key). So, a puzzle, to which those who know the rules are a little better prepared than those who don't -- but not guaranteed a correct reading. The rules for this case would not work too well for tp, I would think, since there are so many overlaps in the language -- one small mistake in figuring out where the divisions were would throw the whole off -- and the number of words that differ only in vowels is high for such a small vocabulary:jnllllllonllt. There are probably some other rules that would work for tp and certainly insertion and transpositions could work effectively (e.g., pig Latin). Of course, with a tp optimized for noisy channels, something like this would work, but would probably not be much of a challenge (nothing at all compared to trying to optimize tp).
I think it is interesting to try to imagine children's games in tp and other pieces of what might be involved in learning tp as an infant (baby talk, mistakes, coaching). Nice question.