This is exactly what M-grades were intended to cover.
You do realize that both make money off climbing via self promotion right? Both get paid to come and speak to audiences about climbing, both have sponsors which pay them to self promote. Any and all press is good press. Will has an absolute gift for self promotion, he always has. I don't fault him for it at all, in fact I think he's one of the most "successful" people to come out of my hometown. I am stoked that he's found a way to make a living from his passions. Will also has a knack for stirring up shit, which is what the name Spray On and the grade were intended to do. He profits (either directly or indirectly) from how much press his climbs get, he has a vested interest in creating buzz and "WORLD'S FIRST W10 CLIMBED BY WILL GADD!!!" certainly goes a long way.
That's your prerogative. I trust Raphael's judgement on grades simply because he has absolutely nothing to gain from hyper inflating WI grades. His silence on the matter speaks volumes to me. He's one of the most prolific climbers in the Rockies and has very strong views on grades.
The implication is that it's M11 climbing.
I can't think of another ice climb that is entirely bolt protected, can you? Climbing ice, but protecting it with rock gear -- sounds like an M-climb to me.
The physical difficulty was equated to M10, it stands to reason that if the climb felt as hard as an M10 climb it probably is.