With respect, in this particular case that is nonsense. Prima facile, using offshore is about tax evasion until proven otherwise, in my opinion.
The Panama Papers didn’t uncover much UK tax not being paid. The Luxembourg Facility had only one, named and known that is, user, Dame Margaret, Lady Hodge, who entirely and absolutely paid all the tax due already and anyway. The Swiss Banks information exchange showed unpaid tax to be about a tenth of what even Osborne was expecting, let alone the La La numbers from the tax justice crowd. Vodafone owed no tax on that Luxembourg stash.
We really don;t have that much evidence of these large numbers for tax evasion….