David, a member of an external assessor org, helped his client remediate a control gap.

Comprehensive and Detailed Explanation:

Assessors must maintain independence and avoid conflicts of interest.

If David assisted in remediating a gap, he cannot also validate the remediation, as that would compromise objectivity.

HITRUST requires separation of consulting/remediation support from assurance/validation activities.

Extract Reference (HITRUST CSF Assurance Program Independence Standards [0141]):

External Assessors may not validate remediation efforts they directly assisted in, to preserve independence.