I believe they will manage it. Most "delays" are caused by low experience and bad forsight of unseen smile Larian may get money from KS (not sure why) but they are also experienced enough by now to make valid estimates.

As I see it the only reason for delay would be some wild new idea worth postponing (and it's less then 15%) or some fatal dissaster.

Also, many people "played" it. So it is not matter of "if they can make an alpha" but "what can they include into alpha". Otherwise it is "ready" now.