Descending black velvet wall with only a 70m?

Any locals have beta on if this is possible and how much shenanigans would occur? I've also got a 40m tag line and some cordalette and am well versed in single strand rapping with a pull cord. We plan to link a few routes and end the day on Epi, so bringing 2 ropes is not ideal. Specifically looking to rap DOWT and I've only been on that wall twice

Thanks, It looks like 50m raps work. I'll be bringing the tag line I guess