Your legal argument is about 3 or 4 stages ahead of where we are now, it won't get to that stage unless PWC do something wrong which is exactly what they are trying not to do by saying they don't have sufficient information to form an opinion. The only benefit of having a QC onboard (most of which would argue the sun shines at night if they could make money out if it) would be to pressurize PWC to make a decision in their favour. PWC won't be impressed by that move IMO & risks antagonising them to go against PNC rather than be supportive & open to their arguments.
The first thing PNC should have done is gone to PWC & say "what more information do you need to form an opinion & we'll give you whatever assistance & resources you need". Not wasting money on an overpriced lawyer before a problem has actually eventuated. Only when PWC had formed an opinion & IF it was to change methodologies should they have even considered approaching a lawyer (not that i believe it would help).
As you posted it's all about interpretation of an accounting standard (not a legal view), so let's see what PWC decide. I just can't help feeling that PNC have just shot themselves in the foot by escalating things unecessarily.
PNC Price at posting:
$2.52 Sentiment: Buy Disclosure: Held
(20min delay)
