If no FISA warrant, then either it was a criminal warrant--which means nothing criminal was found--or it was an illegal tap, which indicts Obama because no honest person can doubt he was running everything. If there was actually no tap, then the anti-Trump crowd has destroyed their credibility with HUGH lies, and thus literally NO anti-Trump story can be given any credibility at all without complete proof.
If in fact Obama (or anyone else) did not tap Trump Tower, Trump flushed out the lie. And his little fib is more than forgivable. After the 2016 campaign, literally ANYTHING Trump does in this ongoing political fight is legitimate. ANYTHING.