Hello,
MS Word works with sections to add columns. All contents in the same section use the same number of columns, you can't avoid a specific content to use the columns but creating a new section.
All licenses include the addSection method to generate new sections.
Using HTML, you need to use HTML Extended (https://www.phpdocx.com/documentation/introduction/html-extended-to-word-PHP), available in Premium licenses, to create sections.
For further support, please send to contact[at]phpdocx.com the username or e-mail that purchased the license and a sample DOCX that illustrates the output you want to get.
Regards.