It's more of the case where reality sinks in, the jobs in US do not pay as much as what he is getting in Singapore. If not why would he spend weeks away from his family just to perform gigs in Singapore.
The purpose of migration is to live and be able to sustain lifestyle by working in foreign country. Not depending on the work in Singapore and living in overseas.
He's got a network in Spore, so its easy for him to make a living here. As he gradually makes his move to the US, I expect he will make new contacts in the US.
When he finally makes the permanent move to the US, it'll be when he's making more there than in Spore. The typical wages in Canada is much higher than that found in Spore & when the US recovers from the recession there will be more opportunities available there.
Sporeans must learn from the hongkies who are now Aussie, Canadian, US citizens. Many of them work in HK because it's more lucrative. There's nothing wrong with being a global talent.