Help me find the App or solution Parker Bear Augmented Reality Bear

Hello and seasons greetings, is there someone out there who can assist.

I purchased a second hand mint condition “Parker Bear Augmented Reality Bear” for my daughter Christmas Present.

The bear was being sold by Apple.Com in 2017 by a company called Seedling, which seems to have been bought out by Homer.

I contacted Homer and hit a solid concrete wall !

The App is no longer on the App Store and the previous owner has subsequently realised they can share it with me or update it etc.

so poor Parker can’t be used and it seems so wasteful to consign him to Toy Story 5 script material.

I hope someone can help to give Parker a purpose and my daughter delighted.

obviously I am happy to pay for the App. But need to be able to download it.

all the best