Can anyone beat this?

I have guys in my guild say it’s pretty easy with GL lead, Zarriss, hermit yoda, grand master yoda and Ezra mix of GK 12 the rest g11. Which is what I’m running. I’ve been at if for 4+ hours and only made it past wave 4 once. Ended up loosing in wave 8 as I lost Zarriss in wave 4 and couldn’t keep my guys alive. Also was told one guy only saw death mark like once in nearly a dozen battles and I get killed by it in every battle. So it’s either RNG just hates me are there is an easy button somewhere I’m just missing. I’m ok with an event being difficult. But after 4-5 hours when you apparently have the right hero’s, the right zeta’s, arena lvl mods on them and still get ran over something doesn’t add up.