I think that the information that you have been given is unfortunately correct. It is likely that you will have to pay the extra cost if you move to a more expensive resort. If you want to wait and see what happens, you may have less choice for moving than you have now. Plus, the other MK resorts are quite a bit more expensive than the WL - if you are looking at anything more than SV it can be a lot of extra $$$.
However, you can always opt to stay at the WL. If you are hoping to get a discount to stay there, it might happen. It seems that some people are getting discount offers to stay. But, do you want to spend your vacation in a resort with construction? Is WL still ideal with construction? If so, then it makes sense to stay here and try to get a discount because of the disruption.
On a side note:
I am surprised that you had transportation issues at AKL. The transportation is usually excellent from this resort partly because The buses only go to Jambo and Kidani. It is a bit further to the MK, however, so the ride is about 10 mins longer. Otherwise we have never had an issue here in 7 different stays.
Good luck with your decision.