When you call utPLSQL.test, you must pass a value of FALSE for reset_results_in:

PROCEDURE test (
package_in IN VARCHAR2,
samepackage_in IN BOOLEAN := FALSE,
prefix_in IN VARCHAR2 := NULL,
recompile_in IN BOOLEAN := TRUE,
dir_in IN VARCHAR2 := NULL,
suite_in IN VARCHAR2 := NULL,
owner_in IN VARCHAR2 := NULL,
reset_results_in IN BOOLEAN := TRUE,
from_suite_in IN BOOLEAN := FALSE
)

Then the utResult results array will not be initialized back to "null". This should solve your problem.