A PR for iOS has not been created yet due to an issue with the GMSPinImage not rendering on the map. Does @caio1985 have an update on whether this issue is under investigation?

I don't have any information on this, but I'm also confused because as I mentioned above, the issue you linked to and that you seem to be referring to here was closed as obsolete in April. I would not expect any active investigation to be happening on an issue that was closed 7 months ago.

Would it be helpful if I created a draft PR for iOS now to make the issue easier to track?

A draft PR would be useful, but also a live upstream blocking issue would be helpful.

Do you think it is worth moving forward with the app-facing package for Android and Web now, or should we wait for the iOS fix?

For now we should wait for iOS, but I also want to make sure there is some clear path forward for iOS and that it's being actively investigated, so we can make a more informed decision on that.