Hello @BeeAmaker,
I hope you're doing well. That DXF is supposed to allow you to select the specific layers you want to see. I'll have to make a bug report about this.
In the meantime there is another way to get DXF output. First, make sure only the Stencil layer you are interested in exporting is visible. Go to AUTOMATE > Run ULP and run the DXF ulp.
Let me know if this gives you the desired result.
Best Regards,

Jorge Garcia
Product Support Specialist for Fusion 360 and EAGLE
Kudos are much appreciated if the information I have shared is helpful to you and/or others.
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