I've done leviathan once without a mic but only calus cp as that's the easiest part and I really struggled to get that group. FYI I have a mic just cba to use it. I've also gone through EOW got to final boss phase and everyone had to go because it took us like 4 hours but the raid had just released that day. My point is if you aren't willing to use a mic or don't have one there is no place for you in raids. May aswell just accept you'll never complete one.