Cover trumps core everytime- keep that in mind. RG is the most influential core dynamic to the overall amount your ball hooks per the USBC Ball Motion Study, however you must keep in mind it was like the 8th most influential factor behind a myriad of other things- mostly relating to surface contact related items (before I get crucified, that's off the top of my head where the ranking is concerned, hence the reason I used the qualification "like," so don't be mad if its 7th or something).
Outside of that, the more abstact world of cores would indicate that there is a big fundamental difference between the cores in shape even if there isn't much difference in the published RG and Diffs. The core in the Vendetta line was very tall and relatively skinny, much like those WW2 German grenades. Theoretically even with little variance in distribution of the mass inside of the ball, the simple difference in overall shape should change its lope and how it progresses in terms of differential throughout axis migration. Short of someone finding a way to reissue that weight block from the Vendetta, it may be hard to create that sort of ball motion again, unfortunately. I did love me some Vendetta.... I couldn't throw it now anyway given my status as a Roto staff member, but I can promise I would sell balls with that block in them, especially in the centers my 2 shops are in. Hopefully that helps.
