Hey Megan,
Summarizing our investigation regarding this case, its not a bug in our system, so after discussed with the relevant teams, partner didn’t realize the data-external-id comes from them (oddly) .
we recommend you recheck the setup,
the test pages config provided to us for SVM_1 widgets show use of only the secondary extId whilst you would usually use both.
LMK if any assist still needed
Thanks