Rebbe Akiva is a complicated sugya – here’s the context, which you completely omitted.
There’s a machlokes between rebbe yossi haglili and rebbe Akiva if the pasuk i mentioned is to be understood the way i said it(that a navi sheker will do miracles) or if we’re talking about a navi who did miracles when he was a real navi and then became a false navi, and told people to rely on his miracles as proof of his validity. This will be a nisayon.
Rebbe Akiva holds that while it will obviously be a nisayon(actually, a bigger one, because he was muchzak as a navi emes) chas veshalom that a rasha should do miracles.
Rebbe yochanan, howeve, paskens like rebbe yossi, and halacha follows amoraim, not tannaim.
So the maskana of that gemara is that a false navi will do nissim.
However even according to rebbe Akiva, there is a big difference. He doesn’t deny that the soton has and will do miracles to test us – his issue is that a miracle can’t be done for those who violate His will, in his exact lashon. The soton not only doesn’t violate His will – he’s doing Hashems will by testing us! There were no specific neviim during Israel’s wars.
Now if you’re going to say that this is a “proof” that Hashem approved of their actions….oh boy. You need to learn some history. Hitler was miraculously saved numerous times from assassins. Does that mean he was doing ratzon Hashem?
And don’t you think the secular army and soldiers were ovrei ratzon Hashem in literally every other way? What difference would the shvuos make? They probably never even heard of them, but you decided that “aha! Hashem wouldn’t have done a neis if they were sinners in the shvuos!”….but mechalelei shabbos He would do a neis for? You need to say like the brisker rov, that the yeshuos are done because there are good yidden living there, but they are in no way a stamp pf approval from Hashem
So cautious chazal were with claiming “God is on our side” that EVEN Chanukah, miraculous win that it was, was only decided the next year to be made into a yom tov, because, as the maharal writes, sometimes the underdog wins an upset victory…. it’s not always indicative of anything miraculous. Only when they felt the kedushah come back the next year, together with the neis of the pach shemen, did they fully accept that a neis had happened and made a yom tov.