When Jesus didn't appear as expected, Russell still believed it (or at least wanted to keep selling pamplets that explained it). He taught that Jesus must have returned invisibly, meaning that Jesus was ruling from Heaven starting in 1874.
Although Russell was intrigued by Dispensationalism, he didn't jump onto the Adventist bandwagon until well after the fact. His first known written pamphlet on the manner of Christ's return was actually not published until the year 1877
Russell, by his own testimony, (Published in ZWT in July of 1906) did not accept Adventist chronology and date setting until he met Nelson Barbour in January of 1876, which again, was after the event had allegedly occured.
It was Barbour, not Wendell who convinced Russell of the dates 1874, 1878, the forty year harvest and 1914 as well as the chronology behind them.
It was Barbour, not Russell who came up with the idea of an invisible Parousia as an explanation of why nothing happened in 1874. (The idea was first suggested to Barbour by B. W. Keith.)