Reproducer attached. This affects both the origin JSON data format, and the JSON parser processor. The processor is the worse of the two, as it causes the pipeline to fail outright. The bug causes a stage error in the origin.
The root cause is in JsonCharDataParser.jsonToField, which includes an if-else string for type coercion, and does not include BigInteger. I'm willing to bet there are other types we should be covering here, but I don't know which ones are missing.