I think he/she went one main gear then nose then the next to be honest pace.
And you can just see his left wing aileron down which seems to me he/she had the controls crossed the wrong way.
So he/she was de-rotated with one main on the ground and lift on the wrong side which the wind got under.
To be honest in those conditions I would have been wing down for about the last 200-150ft.
And the attitude held in the flare power off and in a load voice "get down you whore" stated. Which worked for years landing in Shetland in similar conditions. Which is why for some of us all the fuss about the winds is rather amusing.
I haven't flown a Q400 but mates that have say they are a bit of a sod for tail strikes and it has the handling characteristics of a shopping trolley on the ground rollout. The weather cocking is quite pronounced in x'winds as soon as the mains touch.