Hello,
Based on the content of the fruit flesh "Jaboticaba contains significant levels of certain amino acids like tryptophan and lysine." (
https://www.sciencedirect.com/science/article/abs/pii/S0963996913003487), as well as high levels of tannin in the skin. While both tryptophan and lysine are not always bad, they could be dangerous when ingested in high amounts which is why you would want to regulate how much they eat. Tannin, on the other hand, can be dangerous as we know about tannic acid in acorns causing problems in dogs, luckily tannin tastes different to the flesh which is why dogs are able to avoid it but i am sure this is not always the case. The size of the dog and how much they consume should be considered.
*please note that this research was quick and only identified 3 potential causes for concern. there may be others
*also this fruit is named after the grape but is not related to it otherwise