To be honest, even if a development has no strata title (ie. still master title) and even if the developer bankrupt (can be quite common especially in the previous 97 crisis), banks can still loan you for properties which have good values. So I don't think that was the reason why the bank rejected you. Plus I don't think bank will actually tell you why they reject you. Perhaps your income is not a problem but valuation of the property is. And because you do not want to come up with the extra cash to purchase the property (since cannot get valuation) you deemed it as the bank rejected your application.

Banks do reject lemon projects and some projects which has exceeded their risks. Eg. I do know of a project which all the banks restrict themselves to a maximum of 20% of entire units. And thereafter, the bank will not loan despite how good your background is.

Either way, it is not a vendor's default. You need to do back ground checks on properties before committing. I don't think it will be that easy for you to get back your deposits though you have a 50-50% chance of getting so.