I sympathise with the time spent however, it's meant to be difficult. You shouldn't just be able to walk up to any challenge and grind it out simply because you have acquired the best weapons. You need to know how to use them. If you had spent the first 30 minutes of that 7.75 hours watching a YouTube video of somebody doing it, then spent 15 minutes discussing a strategy with your team, you'd have beaten it. I don't support your stance that it should be made easier to cater for people who can't do it first time without any preparation. I hope you're joking about complaining as I think you'd be (rightly) laughed at.