How to disable the Marketo tracking token without disabling link tracking.
Within the <a> tag, you can add a specific class: class="mktNoTok" and this will disable the tracking token, and yet still allow the clicks to be tracked within the email. If you are proficient with HTML, you may be able to enter this unique class within the header, or other areas of the HTML doc.
You can also disable this through the UI on a per-link basis. Instructions here: Disable Tracking for an Email Link - Marketo Docs - Product Documentation