Wait... You hear the words "Epic" and "Wizard" in the same context and you think he "seems a bit overpowered"? Because his intellect is high? I kneel humbly in the presence of the Lord of Understatement.
Seriously, any mention of the Epic Level Joke Book guarantees that the game has already ridden a horse and cart straight into the middle of Crazy Town. Saying that an Epic Wizard "seems a bit overpowered" is like saying that a black hole "seems a bit on the heavy side". It's true, but it's not really representative of the full facts
Anyway, to address the OP, I happen to have my Joke Book to hand so I'll see what I can do....
You're right about there being no DC for "no save", but there's a modifier for penalising the saving throw. Maybe you could just apply that until the save modifier is so impossible that it's effectively a no-save spell... If your Epic wizard can flange any Spellcraft check (which is pretty easy) then you can just stick 100 on the Spellcraft DC to add +50 to the save DC.
As for the rest, well:
You need the Life seed which has a starting DC of 27.
You want it Quickened, which gives you +28 to the Spellcraft DC.
You want the undead returned to life whether willing or not: that's impossible with sub-epic versions, but in this case we can just allow a saving throw...
So your Spellcraft DC is 55, plus however much you want to add to increase the DC of the save. We'll assume you're going to add 50 to the DC, for a total Spellcasting DC of 155.
GP Cost: 1,395,000 (chump change to an Epic Wizard)
Development Time: 27.9 days
XP Cost: 55,800 (actually, it's - at most - 500Xp, not counting minion abuse, because your Epic caster can and will have made himself a Thought Bottle)
Assuming an ability modifier of +15, that's a save DC of 75 even if you haven't managed to give Kit some bullsh*t bonuses to the save DC's of his spells.
(And don't think I missed the Kit Carson reference either: how very frontiersman of you )
There's another - and in my possibly even funnier - way of dealing with this though. Use Polymorph Any Object (or an Epic version using the Transform seed) to turn the lich into a 51-year-old living gnome, which then immediately explodes.
That way you don't have to worry about the bringing-the-unwilling-dead-back-to-life clause. It's cheesy, but everything involving Epic level spellcasting is cheesy.
Ah that looks about right.
Actually, Kit was a former character of the player who wants to be the gnome that is doomed to be killed by Kit. He's the one that named the wizard, not I. Our grandmother used to call him Sir Kit because Carson is his middle name. I turned him into a quick "Go To" For when i need to change something in my setting, since I hate retcon a lot more than wizards "doing it".
For instance, I ran Tomb of The Forgotten Kings and didn't like the way the Runehound encounter went (CR 3 My ass), and so I changed it to be a meeting between a human bandit, a baby white dragon, and a hobgoblin)
As to how he became so epically powerful? LONG story. Let's just say it involved a LOT of "creating monsters with epic spells and fighting them", then starting a community of wizards to participate in the epic rituals once per year to refresh his epic intelligence buff, so that he can continue the cycle.