So is the primary issue really a "tax code" issue? Is the fix simply a matter of seeking a tax exemption by IRS amending the tax regulations? That can be initiated as a separate bill/rider and subsequent regulatory change. Are there Members of Congress willing to submit such a bill/rider?

Omnibus change is always difficult to muster. Piecemeal through separate bills/riders results in more rapid action and allows the legal system to adapt accordingly.