I'm pretty sure the election was manipulated, but the court only said so because it benefits the incumbents, which control the courts and would lose their power.
It's a struggle between local thieves and putin, that's all. The local thieves will keep us in the EU, which is much better than the alternative, but come on. "More importantly, Romanian courts say so"? Really?
Why do you think that's the only reason the court said so? The election law was pretty blatantly violated (he declared campaign funding of 0, yet tons of ads were bought for him and influencers paid to advertise him).