The main source appears to come from 'A Light That Never Goes Out - The Enduring Saga Of The Smiths' by Tony Fletcher (not a bad read).Now this I hadn't heard. Out of curiosity where's this info from?
"“A lot of people turned their back on Johnny at that point,” noted John Featherstone, who stayed with Marr in Bowdon after the split, in large part to support his friend while holding out hope for a poetic ending to the Smiths. “Morrissey could have, with perfect movie-script irony, knocked on Johnny’s door rather than the other way ’round like it was at the beginning, and said, just, ‘Hey, thanks for everything.’ Or, ‘Can we just talk about this?’ Or, ‘What can we do to make this move forward?’ I remember sitting there going, ‘He’s going to show up. He’s going to knock on the door.’ ” He didn’t.
But in the midst of this period of bitterly frozen relations, it was nonetheless Morrissey who sought to break the ice. He called Johnny Marr on the phone and suggested the Smiths play a farewell gig, at the Royal Albert Hall. Marr declined.
Morrissey continued to hold out the olive branch—or the prospect of one—as he conducted interviews for his first album on EMI, provocatively entitled Viva Hate, released in the spring of 1988 and yielding the top 10 singles he had always suspected would have been the Smiths’ by right had they too been signed to a major label. “I would be totally in favour of a reunion,” he told NME’s Len Brown in February. “As soon as anybody wants to come back to the fold and make records I will be there!” The rhythm section, otherwise engaged at the time with Sinéad O’Connor, would heed his call later in the year, and so would Craig Gannon, the three of them joining Morrissey and Stephen Street to record several songs, two of which would make the UK top 10. When, on December 22, 1988, Morrissey finally stepped onto a stage again, playing a concert in Wolverhampton that granted free entry to those wearing Smiths or Morrissey T-shirts, the musicians appearing alongside him were Mike Joyce, Andy Rourke, and Craig Gannon. Morrissey wore a Smiths T-shirt himself, and came onstage to the sound of Prokofiev. Apart from Morrissey solo material, the group played three latter-day Smiths songs, carefully choosing ones that their former band had never performed in concert.6 With stage invasions taking place throughout, it appeared like a happy reunion of the Smiths in all but Marr and name. But it was not to be. Mike Joyce, Andy Rourke, and Craig Gannon were by then already in the process of taking both Morrissey and Johnny Marr to court for disputed and/or unpaid royalties."
There is zero reference to this assertion in either of the decent books on Marr.