Everything is already there in Genting Highlands in terms of infrastructure (hotels, theme park); this sounds like a complete refurb.
I remember this was announced back in 2014 or 15, and we were in Singapore at the end of 2015 into 2016 and was hoping to get up to KL. First Born got Dengue and got stuck in hospital for a week which put paid to any ideas about seeing if this was going anywhere.