That's a disingenuous reading of what he tweeted and ignores what Jonathan Smith said - Cucurella was number 1, they haven't got a defined next in line but both have stated they are looking at other senior options as well as Gomez. They have been looking at numerous left backs for a while, so it's not true that Cucurella was the only target.
By what has been reported, a fairer reading would be that there are a few similar level targets, with varying strengths & injury records, and City haven't currently decided which to pursue.