Even the ones that do contain wasps can be considered vegan in my opinion. Veganism is about reducing harm and suffering, and these wasps aren’t being harmed. After all, no one is forcing the wasps to fertilize the figs. It’s part of their natural life cycle.
I'm reminded about this beautiful documentary about the fig tree and her symbioses: The Queen Of Trees [1]. This is an official version. It was broadcasted on American TV, and this was ripped on BitTorrent. I can highly recommend watching this documentary. It teaches us how cruel yet intelligent nature (and evolution) can be. There are mutual benefits for different species who suffer or die in the process.
So, if one thinks insects aren't vegan I think you can make a logical basis for not wanting to include figs in your diet.
For hyperbole, if the only way for mango trees to grow was by soaking up the nutrients of dead sheep, and so every mango farm would chop up a ewe for fertilizer once a week to maintain their orchards, than would mangoes still be considered vegan?
As for your example - if the sheep's natural life cycle included being consumed by a mango tree in order to breed then sure, I'd consider those mangoes vegan. If we have to kill the sheep in order to grow mangoes ourselves(but the sheep gets nothing out of it) then I would not consider them vegan.