Can't create backup CRs in fresh Rancher install

[callen-rti]

Rancher Server Setup

• Rancher version: 2.14.1
• Installation option: Helm via Rancher
• Kubernetes Version and Engine: v1.35.5+k3s1

Describe the bug
(Rancher Backup version is 109.0.4-up10.0.4)

When trying to create a new backup CR, this error appears:

You must define a ResourceSet in this namespace to create a backup CR.

Both of the standard ResourceSets are created, but are not in a namespace:

$ kubectl describe resourceset rancher-resource-set-basic | grep Namespace
Namespace:

$ kubectl describe resourceset rancher-resource-set-full | grep Namespace
Namespace:

To Reproduce

1. Go to Apps / Charts
2. Find the Rancher Backups chart and install it
3. Wait for install to finish
4. Go to Rancher Backups / Backup and click Create
5. See error

Expected behavior

• The standard ResourceSets are created in the cattle-resources-system namespace
• The backup creation form appears without error

Screenshots

Additional context
I have tried manually adding the namespace in the ResourceSets' YAML, and get this error:

the server could not find the requested resource