As someone who gives out clones at a patient resource center, I can tell you there is NO WAY to be absolutely sure a clone doesn't have mites.
We have had all kinds of situations arise. One guy thought he had gotten mites from us, but later realized they were in the cooler he took them home in.
Here in Oregon, mites are ubiquitous.
Portland is the 'Rose City'. Mites live on the roses.
Ever heard if Oregon blackberries? The mites live on them too.
They're EVERYWHERE, and nearly impossible to get rid of permanently.

At the resource center, we have a sign up that says...

[align=center]NOTICE!
These clones and cuttings were donated by
the members of Oregon Green Free.
They have been checked for bugs and disease.
However, there are no guarantees.
Please quarantine all new plants until you are
ABSOLUTELY CERTAIN that they will not bring
problems into your garden.

[align=left]This is good advice no matter where you get your clones.
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