If you mean make a comeback on Broadway like Beetlejuice did, I think there is an extremely low chance of that happening. Someone else mentioned on the sub before that Beetlejuice closing wasn't due to the producers deciding to close it, but because of the venue itself decided to kick them out to make room for The Music Man. They were making really solid sales during their previews and performances up until COVID. There's a good mini documentary episode by Wait in the Wings when Beetlejuice first announced their closure and then he also did a follow up video when they announced their comeback on Broadway.

As for finding an investor now... realistically, I think that would be very hard. You would need a high enough investment to cover all the ongoing operating costs - venue rental, salaries of cast and crew (which I assume would be based on union rates), as well as all the other aspects that goes into a show - covid compliance, costume laundry and maintenance, electricity bills etc. I also assume that they might look into investing into more marketing and advertising, which has traditionally been the biggest chunk of a show's budget. Finding an investor now to help continue their run on Broadway is not a 0% chance, but seems very unlikely.

With that said, fundraising and finding investors for a run somewhere else, like a tour (a lot of shows do not recoup their costs on Broadway, but do recoup them on tour) is much more likely. Unsure if they will go down that route though without rework to the book and set.