Mueller did in fact recommend impeachment. That’s what [paraphrased] “I can’t legally indict a sitting President, so I turn it over to Congress…” specifically means.

He just said it in proper legal terms and responsible wording so that the decision to pursue would be Congress’s, versus a forced hand pressured by him publicly demanding Congress’s action and starting the same kind of “mob riot” mentality that got Trump elected.

I.e.
Why didn’t he say the words “impeach”? Because he’s a rational, professional legal mind and not a pitchfork and torch bearing rabble-rouser. The more I read your columns, the more I realize they are mostly an attempt to rabble-rouse…versus rational, analytical, political punditry.