Need some ideas.... im stuck

Second time brewing a high gravity beer. 1.128 (total). Started with california ale on a 2 step (4 liter) starter. "original" original gravity was 1.075. Dropped really nicely and i racked over to buckets (10 gallon batch).

Then pitched 2 vials of WLP099 (Super high gravity ale). From a two step starter (4 liter). Saw noticeable fermentation and started with the feeding of dextrose. 1 pound a day between the two of them (so half pound each bucket). I was shooting for 17% and when i hit 16.9 i did a gravity check and a taste check decided it was done and crashed it out.

Well to my dismay, after a week on more hops i went to rack to kegs and found that it had a very noticeable sweetness left and chances were i didn't ferment out all the dextrose.

So... i put it back in the temp control and slowly raise the temp back up. Washed the yeast and added a 3rd vial, build another starter and repitched. I saw very little action. So then i added 4 packs of champagne yeast. Assumption being, i dont care if it "dries out" a bit as thats really what i want to do dry out that simple sugar which the yeast will prefer most.

saw some action but not much in the way of active which i wasn't really expecting anyway more just praying i would.

lastly, i re-aerated with pure o2 for 30 seconds each and pitched yet another 2 vial - 2 step starter.

i've seen maybe a .002 point variation of gravity after doing all that. Not having tasted it, im assuming it will still be sweet tasting.

So after that novel and stage set. My question.

I've done some research into amylase my understanding of that is to convert starches to fermentable sugars that are in solution and as a result, not the solution in this case as we dont have non fermented maltodextrose (grain sugar) in solution but simple sugar dextrose.

So short of additional fermentation (which doesnt seem to be working) is there any course here i can cut the sweetness? Hide it in hops maybe? i dunno throwing darts here.

 

forgot, current gravity is 1.005. Under most circumstances yeah that beer is done but with 17% alcohol and that much residual sweetness i'd expect to drop below 1.000 to clean up this beer.

 

Appreciate the response vike, yeah it was cold when i tasted it, but not carbed. Im not too concerned about the o2 as this beer wont be sitting on the shelf long its basicaly spoken for already. And i plan to re-dryhop as it just didn't have the punch i wanted. Carbing it is a good option, possibly oaking it too but thats just more time to acquire oak character. Not opposed to time, I just dont want to go down the wrong path and waste a lot of time.