Dependency locking via task doesn't work for one of the subprojects

Gradle versions tried:
6.6.1 & 6.8.3 (can’t update to 7.x for various reasons at the moment)

I’ve been trying to introduce dependency locking to our multi-project gradle. The basics seem to work fine but it felt a little tedious to manually update the lock files every time we change a dependency version. So I’ve been looking into automating some parts and my plan involves creating a task that doesn’t require passing a command line parameter. I can get into more details here if needed but I don’t think it’s very relevant at the moment.

The project structure is like this:

Common.Library               Common.PolicyEvaluator
          |                          |
          |                          |
          |                          |

With a slight modification from the example from the documentation I added this to the root build.gradle:

 subprojects {
     dependencyLocking {
     task resolveAndLockAll {
         gradle.startParameter.writeDependencyLocks = true
         doLast {
             configurations.findAll {
                 // Add any custom filtering on the configurations to be resolved
             }.each { it.resolve() }

For some reason, the task works for Common.PolicyEvaluator and Service.Controller but not Common.Library. If I run gradle dependencies --write-locks it works fine for all projects however.

I’ve been trying all sorts of modifications to Common.Library build.gradle, trim everything that’s unrelated but have not succeeded.
I’m uploading debug logs from Common.PolicyEvaluator and Common.Library. I don’t feel particularly comfortable sharing the full gradle files publicly but I can share relevant snippets if you have any suspicions around certain sections. Though arguably the debug file gives away quite a bit already :).

Oops, can’t upload files as a new user and the size limit won’t allow pasting here. I guess I’ll just mention that Common.PolicyEvaluator has this extra log while the Common.Library does not.

[LIFECYCLE] [org.gradle.internal.locking.DefaultDependencyLockingProvider] Persisted dependency lock state for project ‘:Common.PolicyEvaluator’

Appreciate any help/tips. Thanks.