I have gotten asked about whether I'd OSS my services if I was unable to continue maintaining them commercially. Nope. Not a chance. If they need a soft landing, that soft landing will be a 6 month warning to get your data out, prior to them going into the big bit bucket in the sky. It is extraordinarily difficult to take a multi-tenant SaaS app and turn it into a single-tenant appliance. There are people who do exactly that as a consulting service, and they charge tens of thousands of dollars for it, for a reason. (Plug: take a look at jidoteki.com, which is attempting to productize that particular space.)
Just doing the license review is something that they pay serious professionals with high-three-figures-an-hour bill rates to walk on a file-by-file and function-by-function basis in the case of e.g. an acquisition. If a forgotten subsystem got written by a freelancer 4 years ago and you don't have an IP assignment readily at hand your options are a) locating the freelancer and convincing them to sign additional contracts or b) doing a quick cleanroom reimplementation of code you might not even have know existed.
It's not like OSSing the code will quiet the criticism, either. Some folks simply want to see it OSSed for the same reason they want to see their football team win, but some of the folks have the notion that they're actually going to use it. When it doesn't work (and it won't work), they're going to expect you to fix that for them. For free, naturally. This will often entail doing free tech support for other people's software -- in some cases, other people's very expensive software that they should probably be paying professionals to support for their customers.
If any of this discomfits OSS users, the mint prints out paper ballots which allow you to allocate your votes on desired outcomes for the future. See that some go to the people responsible for software you can't live without.