Learn English – Better way to say “cover our a***s”

A regular Google search gives about 350,000 hits for ‘indifferent between’, while a Google books search gives about 120,000 hits.

I cannot find any dictionary entries that include examples or citations with this usage, but it does appear to be in actual use, if not all that common.

As such, I wouldn’t classify it as ‘truly ungrammatical’, but rather perhaps as ‘best avoided in contexts where you wish to steer clear of potentially controversial grammar’.

In your particular phrase, I would suggest:

X is indifferent to whether (we do/he does/etc.) Y or Z

Or, even more plainly spoken:

X does not care whether (we do/he does/etc.) Y or Z

Edit to reflect edited question:

With the context now known, I would suggest recasting the sentence as follows (vel sim):

The risk adjustment should reflect the compensation that an insurer requires for bearing this uncertainty and reflects the point at which the insurance company considers fulfilling an insurance contract with a range of possible outcomes and fulfilling a liability with fixed cash flows (to be) equal options.

Anything which is going to be enforced is going to seem at least somewhat oppressive but perhaps some options are better than others.

My opinion is that code of conduct is a relatively nice alternative though. I think it sounds relatively genteel at least. The Cambridge Advanced Learner's Dictionary & Thesaurus defines it as:

A set of ​rules about how to ​behave and do ​business with other ​people:

The ​pharmaceutical industry's ​voluntary ​code of ​conduct says ​doctors may not be given ​gifts in ​exchange for an ​agreement to prescribe a ​product.

The literal signification of the words is rather interesting too. It basically means the laws which originates from or belongs to direction, leadership or guidance. The last three links lead to Noah Webster's American Dictionary of the English Language definitions of each word in the phrase if you want more details, although I doubt you will.