Because they both had to do with marriage equality I reckon.
2. How does the DOMA Ruling Upholding constitutionally, each sovereign state's right to consensus on gay marraige mean that California alone cannot have consensus?
The SCOTUS chose not to rule on Prop 8 sending it back to the lower court. The lower court's ruling now stands in CA. That ruling was? That's right, that Prop 8 violated the U.S. Constitution.
Seperate from Prop 8 was the DOMA ruling which, in essence, said that when it comes to the rights, benefits and privileges bestowed upon legally married couples, the Federal Government cannot discriminate against those legal same sex marriages and must recognize them as equal to heterosexual marriages. Basically that legal marriage is legal marriage.
Actually you cannot call the two cases the same in that the were both about marriage equality [gay marriage being legal or not legal, constitutional or not constitutional, and how that is decided: state or federal], and then say they are two separate cases when it suits you.
The simple fact is that in DOMA the constitutional finding was that sovereign states have the right to consensus to decide gay marriage. That Finding was also retroactive. The Court cited that it had always been that way since the founding of our country. So that Finding, a state's constitutional right to consensus on oddball marriages, in question "gay marriage", going back to the start of our nation, applies to any legal situation where a state's right to decide on gay marriage is called into question.
Enter Prop 8 case. THAT IS PRECISELY WHAT THE CASE WAS ABOUT when the lower fed court heard it. The Supreme Court did not make mention of Prop 8's constituitonality. They didn't have to. Anyone who knows Supremacy of law knows the more recent and superior federal ruling nullifies all past ones in conflict with it. That applies to any law or ruling, anywhere, anytime.
When you say the US Supreme Court "punted" Prop 8 back to the lower court, what you don't realize that you're saying is that the US Supreme Court actually did rule on the constituionality of Prop 8. Just because you missed that connection in DOMA's applicable constitutional finding, doesn't make this de facto declaration any more dilute.
Ignorance of the law is not an excuse. Look up the supremacy heirarchy with the federal courts and note that if the US Supreme Court just said something about "issue x" that is in direct conflict with a lower, staler ruling on "issue x", then that lower court's ruling isn't worth the paper its written on from that point forward.
You say "punt" and I say "de facto Ruling"...