I am sorry this happened to you, but from my experience, as a female who also did Dara (i did 3 doses, 8 weeks now, no change right now), I think this might be from steroids, because it was for me...
For me, dara was easy peasy, it did nothing for now but 3rd dose I did without any steroids, because first 2 doses steroids K I L L E D me.
So my background, is, that from regular IVIG (1g/kg on avg per month) i recovered from walking 300-400 steps a day for over 10 years, or even less, to walking 10km a day, or 15km, and being able to travel anywhere, even alone... and then I did dara and steroids (in that condition, I obv still have many complaints so I chose to do it... ) .... and my reaction to steroids is so severe that I could walk for 4+ weeks only 100 steps a day, and had adrenal crisis, lost my period, BP 80/40, constantly feeling like i am in some dream ... It took 4 weeks to bounce back from steroids, despite my quite high baseline! after 4 weeks, I was still at 100 steps a day and NEVER leaving house. And I did only 92mg prednisone total 1st dose of Dara, and 60mg 2nd dose. It was a nightmare, for 4+ weeks I ate 600kcal a day, anorexia symptoms, 80/40 BP, weird responses to salt, so weak i walked 100 steps a day would be avg or less, ... and what is the worst part is that steroids mimic my old symptoms (pre-IVIG) like very disturbed circadian rhythm (like i am living on Mars), my body totally collapse, it mimicked MECFS....
4 weeks later, I got menstruation (3+ weeks delay from the steroids), and after that, my adrenals bounced back too.
So the horror was definitely not related to dara but to steroids, and I am wondering if something is seriously wrong with my hypothalamus to have this severe shutdown (and yeah, I remember reading there could be autoantibodies against hypothalamus?!).
These crises were nearly life-threatening for some days in those 4weeks. I also got psychiatric side effects of steroids that were also life-threatening but i think that's separate from these 'MECFS' /adrenal...ie , one can have only one
TLDR: it wasn't dara. It was steroids and I assume if my baseline wasn't so high step count, I'd crash for much longer.