I think IRS will have a hard time saying it doesn't work. 2202(a)(4)(C) of CARES Act defines "eligible retirement plan" to which CRD may be rolled by reference to IRC sec. 402(c)(8)(B), of which 402(c)(8)(B)(i) is an IRA described in 408(a). 408A(a) says a Roth IRA = an IRA except as otherwise provided in 408A (there's a run-around between account and "plan" and 7701(a)(37) is involved, but that's what it amounts to; check it out). 2202(a)(5)(A) says "any amount" required to be included in income on account of a CRD gets the 3-year spread, no distinctions as to whether must be included because not rolled, or because rolled to Roth.
Also, take a look at 2202(a)(5)(B), which refers to the old 408A(d)(3) Roth rule when they first allowed conversion without income limits in 2010, although I have to say that one has me a little baffled. Basically, under 408A(d)(3), if you did a Roth conversion in 2010 and were supposed to include the income ratably in 2011 and 2012, but took a distribution from the Roth in 2010 or 2011, you accelerated your tax (i.e., you lost all or part of the 2-year spread, because you did not leave it in the Roth). Why that would matter for a CRD (whether the roll is to a Roth or to another type of plan, if, as seems possible, Congress's reference in CARES intended the 408A(d)(3) rules to be extended to non-Roth IRAs and plans as well) is beyond me, i.e., if you took the CRD, thought you could afford to roll it back, then end up taking it out again because your needed expands with pandemic, I don't see why that should accelerate the tax, even if the roll was initially to a Roth. 408A(d)(3) also has a rule for accelerating if the recipient of a CRD passes away before the last year of the spread, which would make more sense. Perhaps that latter part of 408A(d)(3) is all Congress had in mind.
Anyway, it seems hard to believe that Congress would have specifically referenced an old Roth anti-abuse rule in 2202(a)(5)(B), but not intended the 3-year spread generally to apply to CRDs rolled to Roths.