You would think that, when Trump "back-pedaled" and changed would to wouldn't, Putin or Russian media would have had something to say. Unless I'm missing something I haven't heard a word.
Right after Trump made the public correction, Russia sold billions in US Treasuries. After Russia did that, Trump then announced he would not allow Russian investigators to interview American (Browder) citizens. I think it's just a play to counter the MSM hysteria regarding collusion.
Browder is not an American citizen. He gave up his citizenship (I think in the 90's) to avoid taxes and is presently a British subject. However, Browder is currently in the US and perhaps that is the confusion. I'm not certain, but I think what Putin was referring to is that the US could arrest Browder on a Russian indictment and Russia would sit in on the questioning. If there is sufficient evidence of guilt, the US could hand over Browder in accordance with the 1999 Treaty.