QA ULAN direct "get label" queries don't always work

[ebenenglish]

Given ULAN id 500016305:

The "direct" URL does not return an obvious label:

/qa/show/getty/ulan/500016305

But the LD4L URL does:

/qa/fetch/linked_data/getty_ulan_ld4l_cache?uri=http%3A%2F%2Fvocab%2Egetty%2Eedu%2Fulan%2F500016305

This also may be an issue with Curator's parsing of the response in Curator::ControlledTerms::Canonicable#bpldc_label_json_block (app/models/concerns/curator/controlled_terms/canonicable.rb)

[ebenenglish]

problematic ULANs where fetched label does not match display label in Getty UI:

500073675
500028739
500029112
500115546
500029319
500127102
500062493