Thanks for the question.

Fortunately this drilling occurred around the middle of August so that the oak wilt risk from these wounds is substantially lower than it would have been with drilling in May or June. However even now, the risk is not zero. I don’t believe that these holes should be immediately plugged nor treated with an insecticide.

You indicated that your neighbor had their oak treated because of “potential oak wilt”. This is an important point. What exactly is meant by this? If your neighbor’s oak is infected, the probability that something might spread to your tree is much higher than if it’s not infected. You should get clarification on this?

If you wanted to be proactive, have a licensed (ISA), professional arborist make an onsite inspection of these holes and render an opinion. ISA certification is a voluntary professional credential demonstrating knowledge of arboriculture. This certification belongs to the individual arborist and not necessarily to the tree-care company. Look for an individual with experience in oak wilt diagnosis and management, rather than simply general pruning or tree removal. When you call, tell them you have a very large red oak that was accidentally drilled 40–50 times at its base and that a neighboring oak may have oak wilt. Ask whether they routinely deal with Minnesota oak wilt and whether they can provide a written condition assessment with photographs. Do not plug or seal these holes until you get the opinion of the arborist.

See:

https://www.treesaregood.org/Find-an-Arborist

Here is little more information about oak wilt:

https://extension.umn.edu/yard-and-garden-problems/oak-wilt-minnesota

https://extension.missouri.edu/programs/plant-diagnostic-clinic/sample-highlights/oak-wilt-disease

https://hort.extension.wisc.edu/articles/oak-wilt/

One final point. An arborist cannot reliably determine if a symptomless tree, presumably such as yours, is infected with oak wilt. Testing is generally based on appropriate tissue from symptomatic trees. If your tree is not showing symptoms of oak wilt (for example, drooping leaves at the tree's top), testing would not provide any meaningful information.

Good luck. Thanks for consulting us.