I managed to get in touch with Shanne in this forum who was also treated in Singapore some years back.
She was very kind and generously shared her experience and guidance which helped my wife a lot through this difficult time.
It is amazing how this forum connects people who otherwise would never have met, even though Singapore is not a big country. =)
Just some update, we had seen a couple more specialists but decided to go with Dr Timothy Lee.
He is indeed a skillful, confident and caring neurosurgeon. Thanks to him the surgery went well and 98% of tumor was removed while facial nerves are intact during surgery monitoring.
My wife stayed longer than expected in hospital (1 week in ICU and 2 weeks in normal ward) but finally got discharged last week!
She is still struggling with balancing and has some facial weakness but otherwise OK.
The road to recovery may be long but the worst is over and we are blessed to have family and friends support.
So to answer back my question, Dr Timothy Lee is definitely the neurosurgeon that I would recommend for anyone that is seeking treatment in Singapore.