Unfortunately, I cannot see enough detail in these photos to make a clear determination about what could be potentially causing the issues you are seeing in your pin oak.

It could be oak wilt, but there are a number of other issues that can cause symptoms as you've described on oak trees including drought/dry conditions, soil disturbances or compaction (to which oaks are particularly sensitive), insect borers (including two-lined chestnut borer),
waterlogged soil, nutritional imbalances (which includes issues related to iron chlorosis), oak tatters, chemical injury, and anthracnose, among other things.

Below are some resources that can help you learn about some of these issues and potentially determine which may be the most likely cause of the issue. Included in those resources are management options should you determine one of them is the likely cause.

• https://hortnews.extension.iastate.edu/oak-wilt

• https://hortnews.extension.iastate.edu/oak-and-hackberry-tatters
• https://hortnews.extension.iastate.edu/pin-oak-chlorosis
• https://hortnews.extension.iastate.edu/tubakia-leaf-spot-oaks
• https://hortnews.extension.iastate.edu/oak-leaf-blister
• https://hortnews.extension.iastate.edu/anthracnose-shade-trees-0
• https://hortnews.extension.iastate.edu/preventing-grade-change-damage-trees

It may be beneficial to contact a local arborist to come and look at your tree. While this may have some cost to it, having a professional look at the tree in person can go a long way to identifying a potential issue. This link can help you find a certified arborist near you: https://www.treesaregood.org/findanarborist/arboristsearch

If interested, you can send a sample to the Iowa State University Plant and Insect Diagnostic Clinic to confirm what disease you are trying to manage.
It would be best to start with an email and some photos so the clinic staff can advise on the best time and method for collecting and submitting a sample based on the most likely issue. For example, it may not be best to collect a sample for oak wilt testing right now if the symptoms are not more aligned with oak wilt symptoms because it could potentially open the tree up to becoming infected with oak wilt. You wouldn't want to make a pruning cut that allows oak wilt to spread to the tree because you were testing for oak wilt!
More information on how to collect and submit a sample can be found here: https://hortnews.extension.iastate.edu/pidc/plant
Good photos will be important.  More information on how to take useful photos for diagnosis can be found here: https://hortnews.extension.iastate.edu/pidc/digital-photography

Further questions can be directed to your local county Extension office. This local resource can be very helpful since they are familiar with trends and issues in your part of the state. Click on this link to get connected with the county Extension office closest to you and ask your gardening question. https://hortnews.extension.iastate.edu/ask-gardening-question

Happy gardening!
--Aaron