These two instances should be able to match with at least one (or several) of the profiles (particularly Observation-laboratory-uv-ips).  This appears likely to be a validator issue - possibly related to not reliably being able to discriminate by profile for Observation resource instances containing nested has-member observations (not certain why Bundle.entry[0].resource.section[5].entry[1] doesn't also show the same issue?):

INFORMATION: Bundle/IPS-examples-Bundle-01: Bundle.entry[0].resource.section[5].entry[0]: This element does not match any known slice for the profile http://hl7.org/fhir/uv/ips/StructureDefinition/Composition-uv-ips
INFORMATION: Bundle/IPS-examples-Bundle-01: Bundle.entry[0].resource.section[5].entry[2]: This element does not match any known slice for the profile http://hl7.org/fhir/uv/ips/StructureDefinition/Composition-uv-ips

Will suppress these messages for now, as there doesn't appear to be anything further that we can do now to eliminate them (with the current validator).