HPCC-11749 Always recheck persists to ensure locked and exist

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Merge pull request #6135 from ghalliday/issue11749b

HPCC-11749 Always recheck persists to ensure locked and exist

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>