Thank you for your question.  Although grape varieties have 31 known diseases, verticillium wilt is not one of them.  Many species experience leaf browning, especially at the outer leaves, when they have had insufficient water.  Could you please provide more information about your care of the plant?  Thanks!

Thank you for more information.  Although you can have your plant tested for diseases, ai suspect that the water you are providing is insufficient.  Here is an Extension article from California showing the gallons per day (obviously reduced by your plant's size) required to maintain plant health:  https://ucanr.edu/sites/Tulare_County/files/82035.pdf
Drip systems work only if the majority of the water reaches the roots.  None of the photos show it, so I can't tell where it is located.  Covering it with mulch reduces evaporation.  Watering only in the (cool) morning hours reduces evaporation.  Watering in the afternoon wastes water.  Watering at night invites soil fungi infections.  It is entirely logical that browning happens at the farthest distance from the roots:  the only place plants absorb water.  There is just not enough being applied to "stretch" 150 feet--not counting the vertical "lift" to transport it to the leaves.  I hope this helps.  Good luck!

To be efficient (and effective), only water near the roots.  You can't revive dead leaves, but you can prevent this from happening next year.  And pruning off dead leaves won't hurt.