WeWork was supposed to be the next big success for Japanese tech investor SoftBank. Then a planned IPO for the shared workspace firm got pulled as its valuation tumbled. And that leaves SoftBank with a headache. Founder Masayoshi Son is pressing ahead with his massive Vision Fund 2. He’s promised it will raise 108 billion dollars to invest in tech startups. But Reuters sources say he’s struggling to raise the money. Son had promised that Apple and Microsoft were among the investors. But it’s unclear how firm their involvement is, and neither tech firm will comment. Sources say 38 billion dollars from SoftBank itself is the only big commitment so far. Some would-be investors may now be questioning Son’s judgement. SoftBank and his first Vision Fund put over ten billion dollars into WeWork – with returns on that money now looking uncertain. Son still has a track record to boast about though. Above all, there’s the 20 million dollars he put into China’s Alibaba Group in 2000. That stake in the ecommerce giant is now worth over 100 billion dollars.