I think you are vastly overstating your case with these two. First, how well do non-members of the White Council's Senior Council know about the office of the Blackstaff? Heck, even Harry was somewhat sketchy on the concept, so is Eb's position and power level truly well-known? I don't think we have seen anything in the books to indicate that any of the other supernatural entities know what the deal is with the WC's Blackstaff. And even if they do know it, would the rank and file of the Red Court know enough about him to be sufficiently wowed by the bloodline curse taking him out? Second, Harry "started" the war, but he's not the most well-known and capable wizard warrior. Morgan held that role. He was the one who carved a path almost to the Red King himself. Morgan would have been the name that would have wowed folks, not Harry. Harry is well-known in the supernatural world as a thorn in the side of the White Council and something of a black sheep to them.
If the RC was acting as you are stating, they would have targeted the Merlin and/or Ancient Mai. Those are the ones who have name recognition and "wow factor" as being the most powerful and thus, the most impactful. The rest of the supernatural community would not have been impressed with the scale of the spell to kill two mortals, one of whom most consider to be just a pain in the backside thug.
And Kindler is right, this level of overkill to get these two specifically is stupid. If they were truly the targets, there are literally hundreds of ways to do it that are more effective and easier. 2 guys with flamethrowers showing up to Harry's boardinghouse could have taken care of him, and a whole bunch of claymores around Eb's truck set to go off when their electrical circuit is disrupted would take care of him after the Ramps called him and said "hi there - we just roasted your grandson alive".
In fairness, Dresden is highly visible in Chicago, and has a wide reputation, especially among the rank and file Red Court, whom Harry would eat for breakfast. People have heard of him before. And Eb has a big name too (not literally; "Eb" is pretty short) beyond being the Blackstaff. He is a Senior Council member, but he's the youngest, though he's well known as a magical brawler. When the White Council was chasing down Morgan, they sent McCoy, as he's one of the only ones who can be reasonably assured of beating him head on—and Morgan was the one who almost killed the Red King.
The point being that they are high-value targets, but they just aren't high enough to justify the overly elaborate approach. Certainly worth killing, just with a simpler method.
Given leadership that is even remotely competent during the war, they should have annihilated the White Council, simply with attrition and guerrilla tactics. They obviously didn't have that in the Red King. They were so focused on zerg rushing that they didn't bother to be smart about it. Notably, the one time they
were cagey, in the background of Dead Beat, they managed to kill a third of the active Wardens. It cost them a lot to do it, but if they had been doing that the whole time, they would've won in a matter of a year or two.
Similarly efficient and simple tactics would have been more than sufficient to get rid of Eb and Harry, if that was what they were trying to do. Charging up for a big show to take them down in one shot is a waste of time. If they shoot and miss, so what? They lose half a dozen nobodies. It's not like Eb or Harry is going to be
more at war with the Red Court. And if at first you don't succeed...
I should also note from my previous post about Martin "delivering the Fellowship"—that was a ruse, and it wouldn't have worked even if the Red King were poised to strike, but the Red King didn't know that.