Fixes validation of vectorization with contig indexing (#1537)
* Fixes validation of vectorization with contig indexing
True contig indexing needs reference tensors, so finding vectorized
contig domains at the initial validation time can result in false
positives and negatives. Fixed by filling that information at the time
of indexing.
Also considered to keep it separated from indexing and fill it at the
validation time, but it would end up replicating the same logic as reference
replay.
Closes #1534
