I think Meowth would have to think Jesse and James were dead and be so grief stricken that he chooses to give up to make joining Ash's team make sense.
There's already an episode where Meowth briefly joins Ash's companions, but he doesn't let anyone capture him. It turns out to be part of an elaborate plot to steal pokemon, and Meowth goes back to Jesse and James in the end.
I did read one recently, though, where Meowth gets separated from his team, and it leaves Ash bewildered as to why it wants to rejoin Team Rocket. It's revealed that Meowth is actually still a wild pokemon working for Team Rocket to retain its freedom. Ash seriously considers capturing it and training it against its will but persuades himself it would not be for the best, and so he eventually sets off to reunite Meowth with Team Rocket! Ash's black and white world gets thrown into a moral gray area? Best. Pokemon. Situation. Ever. The anime writers should take note, if they haven't already. To my knowledge there exists no situation where Ash willingly inconveniences himself to search for Jesse and James to return one of their pokemon to them! Great way to flip the script!
The Team Rocket trio have a dysfunctional relationship with each other, but they're also kind of a family. They don't consider people outside of their little group the way they consider each other, though, so they're more than willing to steal from, poison, or otherwise inconvenience almost anyone else. unless they have some kind of loyalty or need for arbitrary praise. I doubt Jesse and James would ever do anything seriously evil, like take the life of another human or pokemon on purpose (they've had a few accidents that left Ash and company in dangerous situations), but they're not angels. I think they would make decent anti-heroes, though.
It's also hinted that they are capable of much more damage than they usually do to Ash and company--(they're supposed to be highly trained field agents and they save Ash's life in at least two movies, don't they?), so maybe you could play with that angle? I thought about something where Butch and Cassidy, or some members of some other team, steal all of Ash's pokemon and kidnap his friends. Well, Jessie and James don't like being upstaged, especially if it's their rivals or a gang that isn't Team Rocket (LOL if it turns out to be Team Skull), so that might motivate them to ally with Ash and try to help him get his pokemon back. I think that would also be an opportunity for some interestingly awkward situations. Imagine how your would feel if you were at the mercy of your long-time mortal enemies. I bet Ash wouldn't be too thrilled. This time Team Rocket would be the good guys and Ash would just be along for the ride! Whoever writes this story could even include a plot twist that it was another Team Rocket operative calling the shots all along, and Ash had his pokemon stolen just to see if Jessie and James had gone soft.
I would also like to read a Team Rocket trio redemption arc with Ash catching Meowth as the catalyst.