The first FISA request can be considered a non-story. But when it turned out to be a dry hole, another was filed by the DOJ; ostensibly, under orders from Obama. Either that, there was a rogue in his DOJ.
So no, Obama didn't show up incognito at Trump tower with some wire cutters and a tool bag lol. And he didn't have to in order to be implicated in this.
In either event, the second FISA request was made in October[!] and granted by the FISA court. Again, you have to assume nothing turned up because adverse findings would have made the perfect October surprise.
The whole thing stinks. None of this was a huge secret; the media was dutifully ignoring it because it mucks up their precious Russian narrative.
So, Trump blew the cover off it with a Tweet.