Update ReCaptcha

This should be easy but I just spent about 5 hours on it and I couldn't get it to work. I'm sure someone who knows how to do this can do it very fast... I have a site on a PHP program called SocialEngine3. I have the old Google ReCaptcha on it and I am trying to put V2 instead. I got the new keys and tried to update the code but it keeps saying that the key is not working on this site... as well as other errors when I try different things. There is a template file where I paste a snippet of code and a PHP file for the rest. There is also a [login to view URL] file for the old ReCaptcha that we may need and might need to be updated. Please only reply if you have done this before (and not just ReCaptcha on a regular html file. I would rather you don't spend time experimenting and just do it right the first time if you know how to do it. I also want to make sure the rest of the form doesn't get messed up because it isn't just a regular form. There are several steps that go through a special script. You just need to update the ReCaptcha without changing anything else on the form.