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They aren't known for it, but all trees have the potential to harm structures if planted close enough.

16 feet should suffice for foundations and structures. Since these trees aren't expansive above ground, you don't need to worry much about branch drop that far out. As long as you aren't planting close to a septic system or sewer lines, it shouldn't be an issue.

Here is an article that will give you more information on caring for the tree: https://www.gardeningknowhow.com/ornamental/trees/oak/columnar-oak-trees.htm

Here is an article that will give you examples of trees to avoid near structures and lines: https://www.gardeningknowhow.com/ornamental/trees/tgen/trees-with-invasive-roots.htm

These trees typically grow slowly to moderately. Do you have them both in full sun? A little shade can make a difference.

I would suggest a soil test. There might be something amiss in the soil under the stunted tree. Then you will know what nutrients to supply.

https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/testing-soil.htm

https://www.gardeningknowhow.com/ornamental/trees/oak/columnar-oak-trees.htm