Interesting. Per the study, iron was not that important for growth. But zinc and manganese were. I give mine loads of zinc and manganese (in addition to iron) via Tiger brand zinc oxide and manganese oxide, which has plenty of sulfur to lower pH as well (you can find it at 7springsfarm.com). It can take many months for symptoms to improve though.
If you do use chelates in a foliar application, you typically need to spray when the leaves are tender, in which state they more readily absorb nutrients. Once the leaves are hardened, application results in a freckled appearance, with random green spots where the leaves absorbed some nutrition.
I recently discovered, though, that they fruit much (MUCH) better with a good supply of (slow-release) nitrogen. I believe nitrogen also aids in uptake of other nutrients. They can be salt sensitive, which is why I give mine slow release N. (Note: the slow release junk at the home improvement shops really only has a tiny fraction of slow release N. Look for something with the majority of N in a slow release form.)
When I had mine in pots, they loved osmocote.
Here's some info from the FSHS archive.
JABOTICABA NUTRITION EXPERIMENT by E. D. ACKERMAN (1978)
Ackerman was president of the Rare Fruit Council Intl. in 1980, this is some of the research the RFCI conducted on jaboticaba. At this point the non profit was still working inside the USDA property at Chapman Field.
"Several years ago the Rare Fruit Council, in cooperation with the U. S. Department of Agriculture, Subtropical Horticulture Research Station, established a project to con duct research in various species of exotic subtropical and tropical fruits. One of the experiments undertaken was to determine the difference in effect of 2 fertilizers, supplemented by minor elements, on the growth of the jaboticaba, [Plinia cauliflora] (Myrtaceae).
https://fshs.org/proceedings-o/1978-vol-91/187-189%20(ACKERMAN).pdf