What lambda/exhaust setup does this car have?
Does it have a pair of pre-cat lambda's on a 4-2-1 manifold and a post-cat? Or just a pre-cat and a post-cat lambda?
Dieing MAF would either affect bank 1 on a dual lambda car, or bank 1 and 2 on a tripple lambda car (were banks 1 and 2 are the paired up exhausts in the 4-2-1 manifold). For bank 2 to be failing, I'd assume the car's only got 2 lambdas, one pre and one post-cat.
Not sure how only bank 2 could be affected by MAF. Bank 2 is either post-cat, which is simply reading the delta beween before and after CAT, so MAF isn't relevant, or its on a branch of the 4-2-1, so bank 1 would be off too if it was MAF.
If its only got 2 lambdas, one pre-cat and one post-cat, then "bank 2" is generally post-cat.
Access permitted, simple to change too and cheaper than a MAF.
If its got a tripple lambda, with a pair on the 4-2-1, then you need to identify which cylinders are "bank 2" of this branch, then it could be injectors on one of these.
I'd go for the post-cat lamda though personally. If the car has been sitting a while (a few months) maybe it just needed a good warmup to dry out this lambda.