I think casinos will eventually pick up, as Chinese love to gamble and the government in opening the two integrated resorts backed this horse.
I'm sure your skills are transferable but Singapore is fortunate that it is the highest paid country in the region so the talent flocks here regionally, which might make it tough. Especially with the focus on retaining local staff.
Reverting back to your point about CPF, I suspect she probably didn't contribute as she was employed abroad (unless she was employed as an expat in the UK). But it's probably less of an issue.
Just focus on supporting her to get a job and at home. Once she has returned, just get her to apply for your PR and then you'll be sorted. As long as she has a job in Singapore you should get your PR.
Good luck in any way you approach this. It's a difficult time for everyone so I wish you all the best!