Is the presence of leftover camel meat in the mouth, or meat of unknown origin or its derivatives such as gelatin, or camel meat broth, or the regurgitation of camel meat from the stomach considered to invalidate ablution?

Wudu' from camel meat is obligatory, whether the amount of meat is large or small, even if it is between the teeth, as long as it has substance and was swallowed by its eater. This includes small pieces in the broth.

As for meat returned from the stomach: if it reached a place where a person could expel it but did not, and swallowed it, then wudu' is obligatory. If it did not reach this place and remained high in the throat, then no wudu' is required.

Broth free of meat does not necessitate wudu', nor does camel milk.

As for meats of unknown origin, wudu' is not required from them until it is known with certainty that they are camel meat.