I have similar knowledge to yours but the point I make still stands. I recognize the limits to my knowledge and am aware of my own ignorance. I do not have access to the classified information necessary to form an opinion on what happened. It is for lack of a better phrase a case of he said she said.

Maybe if politicians weren't so willing to lie to us it would be easier but the fact is that there could be political motivations behind some of what they say in the media. So we have different hypotheses about what could have happened and you can come up with evidence to support them. My current opinion is that it is likely the hackers were Russian but it's unknown whether or not they were state sponsored or had anything to do with the Russian government.

When I see news articles which say Putin ordered it or which talk about sources with access to classified information leaking to the press it is very hard for me to know what is or isn't true under those circumstances. My own logic would conclude that it is very likely that hackers made a mistake and the IP address or other information such as the tools used could link them to Russia. It doesn't from that information alone mean anything else.

Your hypothesis makes sense. So does the hypothesis of the other side who claim the Russian government authorized it. But unless I personally have access to the classified information or they release a declassified document so I can see with my own eyes there is no basis for me to form a strong opinion. My official stance is I do not form strong opinions with incomplete information.