Ok so what he just posted i've tried, I did the exact same thing. My phone wouldnt mount in twrp, couldnt get download mode to work, so the easiest and quickest way is to order an otg cable.
Here is my post of me trying to figure this out, finally solved it. Spend the $1.69 with free ship from ebay for otg. format flash drive to fat32 then put your rom and mount the otg.
You can fix un-educated, but you can not fix stupid!