For your "fake solar" cord, are you positive (pardon the pun) that you have an XT60i cable?
From what I understand, the extra middle pin on the XT60i plug is what tells the Delta 2 if your input is car or solar.
I just picked up another EcoFlow Delta 2 on the eBay Memorial Day sale. For a baseline, I purchased a new Delta 2 last year from Amazon and have had no issues with it for the last year running my sump pump. This refurbished one from eBay, though, stinks! Not in operation, everything seems to be...