Fix GSAP Parallax Sync Issue

I'm looking for a skilled web developer to fix a GSAP parallax effect on a wordpress PHP template.

Requirements:
- Left side content should rise in sync with right side image descending.
- If left is "up" by 20%, right should be "down" by 20% and so on. and both sections shuould reveal themselves to 100% at the same time.
- Currently, the right side descends later than the left.

Ideal Skills:
- Proficient in PHP, GSAP, and JavaScript.
- Experience with animation synchronization and cross-browser compatibility.
- Familiarity with JavaScript libraries/frameworks (jQuery, React, etc.) is a plus.