You can't make assumptions about an airlines profitability based on the prices on 1 route over 1 week, when Aurigny have 8 routes, and flybe have 170+. It also stands to reason that flybe will have a greater share of the Guernsey Gatwick market that originates in the UK, due to their far greater brand awareness and marketing actiity there.
But if I was a betting man I would think that Aurigny's current financial problems are more to do with another airline that is making similarly large losses flying 12 x J31s a day between Guernsey and Jersey, whilst "buying" all the corporate business.