I will revive this topic because someone else will look for a solution and this is high up when you search for this problem.
You can re-set your rl_dna file from the attributes, here is a video explaining it:
VIDEO
Process:
- Open your metahuman file, select the face mesh object.
- Open the Attributes Window
- Find the rl4 Attribute
- Change the DNA File Path.
- Success!
Troubleshooting:
On my rl4 attribute it says unknown, and it does not show a path to replace:
You probably do not have the Quixel Bridge plugin. Solution HERE.