Er, no. Russia INVADING Ukraine means starvation in Africa. If Russia LEAVES, the starvation ends. And letting the Russians HAVE Ukraine doesn't guarantee food exports will increase. In fact, it's likely to go the other way.
...exactly my thoughts, when I read the arguments.
There will be (at least) a year's blip as infrastructure and agriculture has to recover, but the chances that "Ok, Ukraine is Russian now" leads to any better outcome for Africa (slower recovery, worse restoration, grain will doubtless get funelled through Russia's hands to prioritise
their conceptual needs above Africa, what does go out there will be tied to 'goodwill' agreements of the Kremlin's choosing of both open and back-door nature, etc...) is fantasy.
The chain of "help Ukraine => harm Africans => who will pester us" smells of hedging the racism card. "I'm not racist, I just don't want brown people coming here." I don't know much about the political tendencies of these Italian opposition guys (I bet it's more complicated than my mind is painting them) but if I'm summarising the summary of their arguments at least half-way fairly then I'd be looking at where strings are being pulled, or even let run free a little.
Charitably "opposition for opposition's sake" might be the only thing (taking a contrarian stance), but it's a bad counterargument to push when there's always plenty of other levers to operate to put internal pressure upon pretty much any government, and Italy is one of those that always seems to be on the edge, or jumping from one edge to another. They could afford a (pretended) solidarity on the Ukraine issue.
The worse position is that there's a populist pro-Russia groundswell (or even more vehement core base) such that they
can't claim the same moral position on this issue, or lose their lifeblood perhaps to more marginally-inclined coalitions of political movements. I've really not heard much about that. I've no doubt there's such pockets silently fuming in all 'western alliance of support" nations, with their own 'reasoning' behind their stance. And no doubt there's been a concerted effort by Russia's usual assets to find and then stir such pots as exist that are already simmering with the right sort of recipe for their purpose. Enough for a civil war? (Within Italy, or within/across the EU in general, ignoring Erdogan for the moment.) Worth a nudge, though, I'm sure is their attitude...