John, there are at least two ways to do this (and I very much encourage you to use as few forms and unique LP objects as possible).
For both methods, add conditions when setting up the form's Thank You URL. Each URL differs by the query string (https://landing.example.com/thankyou?report=report1, https://landing.example.com/thankyou?report=report2).
Then, to render /thankyou.html differently depending on the value of report, you can either:
1. Create a segmentation called report with each possible value as a segments.
2. Use standard browser JS/CSS to change the page layout based on the query param. You can even do this without JS using the #hash and the :target selector.
If the choice of the follow-up is based on a value entered in the form, you also can use dynamic follow-up, available in forms 2.0.
Hope this helps,