Trump has done a great job at defeating himself. The article is correct they have enough evidence to indict Trump on Obstruction of Justice. You know when you get on an NBC interview and admit you fired Comey over the Russian investigation--I really don't think there is clearer evidence of Obstruction of Justice, and really am not certain what Mueller is waiting for on this one.
Comey did mention to others--regarding Trump pressuring him to drop the case on Michael Flynn, and when he didn't, Trump he fired him. Then they made up this ridiculous excuse that Trump fired Comey because he was mean to Hillary Clinton. That didn't fly--so he decided to do that NBC interview--

That is Obstruction of Justice an impeachable offense.
James Comey testimony: Trump asked me to let Flynn probe go - CNNPolitics
Deputy AG briefs the full Senate after whirlwind week of controversy
So you believe the people not involved with the investigation? So sad. Who leaked this info?
You can avoid that video I just posted with Trumps lips snacking in sync with the words coming out of his mouth. He admitted he fired Comey over the Russian investigation, which is, Obstruction of Justice. That NBC interview won't ever get erased. Richard Nixon was never stupid enough to accept a televised interview and admit guilt.
This investigation is moving at the speed of light compared to Watergate which took 2 years 7 months before Nixon was forced to resign.
Robert Mueller has been in charge since late May 2017 and he has already delivered 3 criminal Federal Grand Jury indictments and one guilty plea, with more to come.
A good movie for you to watch about right now is "All of the President's Men."