http://news.sina.com.cn/c/2013-02-25/131926352819.shtml

Brief summary:
On Feb.23, SQ836 departed SIN bound for PVG on time, but diverted to HKG due to weather. Then diverted again to ICN. The were over 200 PAX on that flight were Chinese passport holder. SQ accommodated other PAX at ICN, but left those Chinese PAX in the ICN airside. Those Chinese PAX cannot leave ICN due to customs issue and they were stranded in ICN for 31 hours. The end results: stranded passengers received 12K WON meal vouchers at ICN, and further 150 SGD for lodging.

My question:
1. Why SQ did not reroute those stranded PAX onto OZ/CA at either HKG or ICN?
2. There is an airside hotel at ICN. If SQ can provide lodging for those PAX who were able to leave ICN, why not accommodate those Chinese PAX to the airside hotel?
3. Why not divert to PEK instead?