I would be stunned if Morrissey and Marr ever worked together again.
However, with the obvious exception of Mike Joyce, I don't think Morrissey particularly has anything against any of the ex Smiths.
If he happened to bump into Andy Rourke, for instance, they'd probably have a drink and talk about old times.
I think after all the criticism Morrissey has had from the media and from some (former) friends in recent years, that he probably now thinks more highly of those people who haven't come out and kicked him while he was down. People whom, when he was more popular ten or fifteen years ago, he probably wouldn't have given the time of day. I think he now realises that he has a kinship with those people that he may have mistakenly thought was lost.
Alain Whyte returning to the fold is a good example of this. At no point did Alain slag off Morrissey in the press or on social media over the last few years. I think Morrissey appreciated that and clearly felt it was worth reconnecting with him as a result.
"Hold on to your friends"