The impeachment will only happens when the GOP lawmakers in both the Congress and Senate have the will to do so.  Without their will, no finding but short of bags of Russian money under Trump's bed by Mueller will make it happen.  Their will might be strengthen lately with what Trump did recently as described in this article, including their 'shell shock' moment.  To them, they will be dumping the President who is damaging the party, but will say it is for the country of course.  It will be funny and ironic that when the war with the GOP heat up Trump will just leave the party and form his own, paving the road for his children to continue the dynasty, believing that his personality cult ( with his most ardent base) will carry him through another presidency since votes will be siphoned off from the GOP.  That will be the nightmarish scenario to the Republicans.