The movingAverageDuration and observationFrequency are uint48. So movingAverageDuration / observationFrequency may overflow when casted to uint32. In the below snippet, line 281, the array will be set based on the uint256 value, but the numObservations is casted down to uint32. It may result in different numObservations and the length of observations array.
However, given the large numbers, the attempt to set such a large number as the parameters will likely to fail with out of gas error, since the length of the array observations is ridiculously large in this case. Yet, it is probably safe to set some upper limit for the numObservations or use safeCast.
