Steel Path Ropalolyst Mission Failure Imminent issue

[(NSW)Illusn]

I've been trying to solo the steel path Ropalolyst, but each time I try it slaps me with a mission failure imminent approx 15 minutes into the boss fight. The boss fight drags on because of the amount of time it takes to whittle down the shields (for context, I have a decent amp - not the best, but not anything to sneeze at either) and I get the mission failure imminent, regardless of whether I kill the smaller enemies in the fight prior to this.

This essentially makes the fight unbeatable on my own, even though I would be able to take it out pretty easily if it weren't for the mission failure imminent prompt. Please fix this DE! If you're going to have absurdly tanky enemies, then don't penalise us for taking a while to take down the steel path bosses. I shouldn't have to get a squad for the fight just to counteract this arbitrary timer, especially with how hard it is to get a squad on Switch.

For context, this screenshot is taken during the second phase of three of the fight:

[(PSN)SergioMApt]

You must kill any smaller enemy once in a while, sentient, amalgam or corpus.

[(NSW)Illusn]

3 minutes ago, (PSN)Councillor_S-MA said:

You must kill any smaller enemy once in a while, sentient, amalgam or corpus.

Yeah, I did. That's what made me think it's a bug, since all the fodder enemies were killed during the first phase. Maybe it doesn't count kills and kill assists with Equinox's duality augment? I've noticed that kills with the duality clone also don't count towards nightwave kill counts.

I beat it this morning using an eidolon hunting Volt build, so at least I didn't have to deal with the issue for long.

[(PSN)SergioMApt]

2 hours ago, (NSW)Illusn said:

since all the fodder enemies were killed during the first phase

that's my point. After that you kill no more small enemies for a certain X period of time. Game kicks us for idle time and no kill time (I guess).