He is most certainly soloable even below lvl 42.
I just tried on my new baby alt “Bad Wolf” - who is level 25 and about to do Eleanors mission and she completed it with no problems
Gear and abilities are pictured below:
You can see here i have one heal ability, i use the sedative delivery to apply debilitated (not much use here though as the bosses in Storymode don’t do all that much damage to you) it’s useful on adds to slow them down while you gain some distance to do more DPS - there are other, better options, i only have it slotted coz the toon is new and it’s what she has for now and by force of habit i often press it, even though it’s not doing much - yet)
My tip is - DO NOT drag him up anywhere.
That is a tactic used for higher tiers only.
There is also flames behind you from the blue door you entered, both flames eventually meet in the middle - that’s why people drag the Corroder up to a midway point.
If you want to kill him, coz he aint going to kill you in story mode - go for the jugular 
start the fight immediately and edge him backwards while you keep an eye on the flames behind him. Do as much dps to him as possible while leading him away from flames.
You should have no problems, I had plenty of time left.
If you are still struggling, drop me a msg and we can grp up if you like - i’m often asking in the starter zones if anyone would like to do dungeons - I’d be on level too, so it’s not like i would be butter knifing my way through while you hoover up loot - coz that’s just no fun at all.