TestNG IAnnotationTransformer2 transformed value reverts to default - annotations

Question

In summary, my implementation of IAnnotationTransformer2 picks up a test method annotation and modifies it successfully, along with all other method annotation transformations. Then at test execution time, the annotation value reverts to the hardcoded value, but only for the one method, not for any others. The other methods use the transformed values successfully.
Details:
I have a TestNG test class ServiceTest with a number of test methods (>25).
I also have a custom annotation #QueryFile which takes a list parameter containing an array of String which reference paths to text files containing parameters:
//ServiceTest.java snippet, original:
#Test (dataProvider="QueryTests",groups={"json","api"})
#QueryFile(list={
"/test/inserts_multiquery_json.txt",
"/test/selects_multiquery_json.txt"
})
public void testWithMultipleQueries(String query) throws...
Previously, as in the example above, the list values were hard-coded into the ServiceTest class, with a separate set of paths for each method.
Recently, I have added a implementation of IAnnotationTransformer2, QueryFileTransformer, to load these paths from a properties file instead. This makes the job of toggling test parameters on and off significantly easier (e.g., I can just rename various versions of the properties files to the expected name and it gets picked up.)
Revised ServiceTest.java
// revised ServiceTest.java snippet:
#Test (dataProvider="QueryTests",groups={"json","api"})
#QueryFile(list={})
public void testWithMultipleQueries(String query) throws...
...
#Test (dataProvider="QueryTests",groups={"json","api"})
#QueryFile(list={})
public void testWithJSONParams(String query) throws...
TestNG_toggle.properties
// TestNG_toggle.properties snippet:
# General tests
testWithMultipleQueries=\
/test/inserts_multiquery_json.txt,\
/test/selects_multiquery_json.txt,\
/test/updates_multiquery_json.txt,\
/test/deletes_multiquery_json.txt
testWithJSONParams=\
/test/inserts_multi_json.txt,\
/test/selects_single_json.txt,\
/test/selects_multi_json.txt,\
/test/updates_single_json.txt
So here's the problem: One of my test methods, and only one, suffers the indignity of reverting to its default #QueryFile annotation value during test execution. All other methods honor the annotation value resulting from QueryFileTransfomer.transform. In the example above, testWithJSONParams executes correctly with the values from the properties file, but testWithMultipleQueries executes with a null list, and is skipped. When testWithMultipleQueries has a hardcoded list, it works fine.
Some facts:
Execution is through maven surefire and failsafe
preserve-order="true"
as stated above: QueryFileTransformer picks up the testWithMultipleQueries annotation and modifies it successfully, in the midst of all other transformations. Then at test execution time, the annotation value appears to revert to the hardcoded value.
stepping through the eclipse debugger, it seems the transformation of testWithMultipleQueries occurs earlier than other method annotation transformations, but it's not always first. Often it is intermingled with methods from other classes, which are listed first in the xml file, whereas the rest of the ServiceTest methods seem to transform in sequence.
Specifying the method as exclusive in the xml config file had no impact other than the expected of omitting the other methods' execution.
UPDATE Further debugging implies the instance the test method passed to the DataProvider (and it's declared annotations) is a different instance than the one with transformed annotations. This is not the case with the methods that succeed.
Any insight you can provide will be most helpful.
Thanks!