So, isn't the trick here getting 1) someone high up / creative type at the copyright owners level to notice this and give approval before the 2) lawyers / corporate sharks at the knee-jerk level send a cease-and-desist or copyright notice and decide to shut you down and steal the idea to develop themselves?
Because I imagine what lawyers worry about is (at worst) whether letting you go on with this website shows that they did not assert their rights in the face of a derivative work, or (at best) whether the trouble of negotiating with you on the terms you want for the development you've already done is more trouble than just taking the idea and doing it themselves?
I would guess you have a bit of a ticking clock to spread as much word about this and try to reach the person in the first category (through contacts, "phone-a-friend-who-might-know-xyz", etc), before inevitably the 2nd category catches wind of it.
I imagine that with lockdown rules, it has more chance of being noticed and approved. It'd be cool to see Larry or Jerry mention it. Even cooler if they wanted in.
Because I imagine what lawyers worry about is (at worst) whether letting you go on with this website shows that they did not assert their rights in the face of a derivative work, or (at best) whether the trouble of negotiating with you on the terms you want for the development you've already done is more trouble than just taking the idea and doing it themselves?
I would guess you have a bit of a ticking clock to spread as much word about this and try to reach the person in the first category (through contacts, "phone-a-friend-who-might-know-xyz", etc), before inevitably the 2nd category catches wind of it.
Good luck with it though!