Not sure what agreement they have there, but at the end of the day it’s Wine which has decades of open source development behind it at this point. Plus a bunch of other libraries (gstreamer being a notable inclusion) that are all FOSS. This still fits the pattern of Apple profiting off of OSS projects while contributing back as little as they can get away with.
A non-trivial number of contributions to Wine come from CodeWeavers (30%+ of all commits), which in turn is funded by its work on Crossover, Proton, and commercial agreements with other businesses. Wine would not be the project it is today without the contributions of CodeWeavers. Contributing cash to the companies contributing code is a perfectly adequete form of giving back.
CodeWeavers released an annoucement when Gaming Portal Toolkit was announced.
https://www.codeweavers.com/blog/mjohnson/2023/6/6/wine-come...