Before you do anything can you answer a couple questions...

Where do you live? The upper part of the transition zone stretches from coast to coast and up and down the coasts.

What kind of grass do you have now?

What is your current watering plan? How often and for how long do you water? Are you planning to return to that once the new grass is stabilized?

How high/low do you mow and how often?

Have you used fertilizer in the past year? What kind and when?

I'm asking these questions because I suspect you're doing something culturally wrong which is causing the grass problem. If you continue to do the same thing with new grass, you'll get the same result.

Eastern Panhandle of WV (Martinsburg) I planted Lesco Tall Fescue Mix 2 years ago completely, which is what I have now. I mow the grass 3.6 inches in height.

Normally, with our rainfall, i don't have to water as much, but even with watering the yard starts to die with drought symptoms, and it starts to thin out and never recovers. When I know it's not going to rain for awhile, which happens in July, I water at least 1 time a day for about 10 minutes. There's no fungus infection, and soil testing the dead areas doesn't show any problems (according to logan labs).

I use milorganite fertilizer 3 times a year, the last time i placed an application was June 1st. Last year I was using the same, and the yard was in better shape, but the highest temp last summer was not nearly as hot as this year.

Maybe wait till fall (late summer) and plant a tall fescue/ bluegrass mix blended for your area. Find out what type of blend local sod growers are using , and usually you can find the same seed some where. ( sometimes on line) Local sod growers will be using the turf types most likely to survive in your area. Make sure the soil is loose , as any kind of grass is going to struggle on hard ground. Go thru all the steps you mentioned above before planting.

West Virginia is really more fescue country than Zoysia country, if you want my honest opinion. Zoysia turns straw brown at first frost and stays that way until last frost the next spring. Fescues can look very nice over the entire year, but may take a bit of a beating in July.

One problem you're having is improper watering--you have the grass trained for short, weak roots. Optimally, you'd want to water once a week (tops), but you have to adjust it to get it there.

Right now? Drop to every other day watering for 20-25 minutes. In about two weeks, if it needs irrigation, go to every third day for longer. And so on, until you reach seven days. That's about the best most people can expect in hot weather, although cooler weather won't require nearly that level of watering.

Your feeding is off a little bit, but with Milorganite that doesn't matter so much. Still, the optimal dates would be May 1, September 1, and October 1 for you. Then winterize when the grass stops growing but is still green with any good synthetic (it's too cold at that point for the Milo to work very well). That'll increase your winter survival and color.

However, if you have your heart set on Zoysia, so be it.

I don't know Zoysia types, so I can't say if Zenith is the best choice for you. Below I just ran with it, but listen to anybody who says you should choose another cultivar.

Zoysia is a warm season grass, so I'm not sure if you have enough of the season left to get it strongly established--it's almost August. It might be wiser to wait until June of next year.

I see that Zenith Zoysia is available in both sod (and plugs as well) and seed. Zoysia, well-fed and well-watered when young, spreads like crazy in any sunny area, so even poorer germination won't matter too terribly much.

You'd definitely want to use Round Up, but there's no need (or desire) to till. Just mow the dead fescue as short as you can and bag the dead stuff to avoid having hay all over the place. Then seed straight into the dead stems of fescue, which will help hold the seed and keep the soil from eroding.

Starter fertilizer might or might not be required (we'd need a good soil test to be sure), but I don't object too much to using it once at seeding, particularly with the dead fescue stems still there. The phosphorus won't erode very much as long as there's cover.

Seed will require two to three daily waterings, lightly, to keep it moist through the period (top dressing with compost or peat moss can help hold the water but is strictly optional). Plugs will need to be kept moist until they establish, and benefit from a slightly moist environment and being well-fed while they spread.

I have a lawn in lower NY that has zoysia in large patches, and while it stays green in the heat, it is brown until very very late in the spring (well into May) and all throughout the winter. Given the amount of time that zoysia is "off season" here (and probably in WV too), it's much better to find a good cool season grass that will survive the summers and only look beaten down for a short period during the heat. This approach will get you a nice looking lawn for a longer period of time.

Outsidepride.com has a line of seed called- "combat extreme' . There are 3 different formulations depending on your area...... most have a mix of blue and tall fescue. The one for transition zone, has the newer type tall fescue that has lateral spread (similar to bluegrass. )

For fescue, cut as high as you can stand seeing it! It's the watering method that's the problem here.

If you water really often (daily), the grass won't bother to invest a deep root network. Same goes for a lot of other plants, really. Once grass has established a deep root network, it can survive on once a week watering (but it should be a large watering, an inch is common, and you should measure it!). You want to encourage your grass to invest in roots. Roots cost the grass energy, so it won't grow more roots unless it sees a need (decreased watering frequency).