As the OP on this thread, which is now over two years old, I'm underwhelmed by the responses. To be clear, I'm appreciative of everyone who has responded, and respectful of the time and intellect expended by those who tried to find a way to make the parser work. However, at the end of the day, it is the Spamcop devs who need to fix this problem, and if they even exist anymore, they are nowhere to be found. They certainly aren't active on this forum. Indeed, it seems the lights were long ago turned off over there.
As for the advice to try removing the first Received line, that didn't work. I tried that, and also removing the first 2 Received lines, then the first 3 Received lines, and finally all lines which referenced my email host in any way. That last trick worked, with the parser properly recognizing that Sparkpost was the source of the email. But then Spamcop decided amazonaws was the correct reporting address and all reports for amazonaws are devnulled. Here is a link for anyone who wants to look. https://www.spamcop.net/sc?id=z6549409030zca1b5ca2a3591ef1dad9030579e84550z
By the time I find and delete all the references to my mail host's server farm, especially when Spamcop incorrectly redirects the spam report and then devnulls it, I'm better off just complaining directly. Spamcop has become useless. No doubt Julian Haight is crying in his beer.