To me it seems that the seller may have muddled up the tracking numbers when adding them to their sales notifications on Ebay ?
So far as the EVRI tracking is concerned they do usually take a photo and/or the GPS location in relation to delivery. IF thats not yours then personally i would open a claim through my payment provider who would look far closer at the evidence than Ebay and their bots.
Out of interest when you purchased your item did the listing say it would be delivered by Evri or Royal Mail ?