We are still uncertain as to what Mueller said... given lawyers prefer to win, it seems he may have opted to not ‘bring charges’, in the spirit of what the justice department could convict on. However, impeachmet procedings have a different set of parameters, both in what constitutes guilty, and what is an offense that is convictable. The same evidence might lead to a different conclusion... or, be evidence of yet other crimes outside the narrow perview of the special counsel