I think some will come back, maybe not all at once. He won't want to just discard people who stepped up when he needed them to, imo. Some of those names there will be easy -- Umunna was never really someone who was always mouthing off to the press for example. Clive Lewis is a Corbyn supporter, he just left the front bench because he had half an eye on the remain vote in his constituency. Corbyn apparently gets on quite well with Liz Kendall, even though she's at the other end of the spectrum, politically. Jess Phillips was too much yapping away negatively to the press, but on the other hand that'd show a big willingness to heal the divide.
As I say, the main thing for me is that they work towards the policies that have been campaigned on, ones that energised the youth vote and attracted red ukippers. Their job is to bring along more voters to these ideas and I think it can be done, particularly if they have a sensible plan for a softer Brexit.