Hello Aaron
I haven’t personally implemented something like this, but doing some research, I have found some developers creating an IP SLA responder for Linux. If you do a search on Github or Gitlab you’ll find some. Or use your favourite search engine to find ip sla software for linux. Since Raspberry Pi uses Linux, it can be applied to them as well. It may take a bit of research, but it can be a very useful thing to develop!
I hope this has been helpful!
Laz