The risk would be if the home or business owner did nothing else following your extraction.
If problems developed later I suppose a dishonest customer could claim they thought you took care of the problem incorrectly by removing the water but not completely dry their home or business. Also that you did not do your due diligence by informing them that more would need to be done.
Some people truly would not know they difference of what they were purchasing from you and it could happen. Doubtful, but always a possibility.
You're probably better getting the training and doing the whole job, if it's larger and beyond your ability then pass it off.
Just doing a part of what is necessary, is a lot like you preconditioning their carpet and then telling them they need someone else to come in and HWE out the soil. :shock:
Weigh your risk, if it's a small area of commercial glue down carpet and they have good air movement minimal risk. If there are a lot of materials wet, walls, ceilings, carpet, pad, you might be in over your head.
It's really not that hard to do it all, remove the wet materials that can't be dried, and dry those that can be. Monitor the drying with meters and when the meters tell you it's dry, it should be.