The evidence you've shown suggests the problem is not WebGL 2. The screenshot you showed says WebGL 2 is not supported on that device, so it won't be used. If it's not used, it can't be the problem. So we go back to square one and basically there's no indication at all what the problem could be from this post.
As ever, the best approach is to make the smallest project you can that demonstrates the problem, and share the project file so other people can try it out.