For the club to say it's not possible that mites were transferred to you via their shop is pretty bold. Mites and their eggs are TINY and a grower walking into the club with mites on his CLOTHING AND HAIR could potentially even lead to an infestation! My own mites, which I have now suffered for a year, came from visiting a friend who had them, even after stripping buckass nekkid at the bottom of the stairs before going into my apartment!

A trained eye might recognize the style of certain clone providers' products- how many nodes does the clone have? Does it show stress symptoms? Are the leaves clipped at all, how many, and how aggressively?

Strains also have different appearances and while you can't say that IS a specific strain, you also CAN say that a clone COULDN'T POSSIBLY be another.

Always quarantine clones when bringing them home, preferably in another part of the house, or a different building entirely, and I recommend treating with a systemic miticide [AVID] or pyrethrin bombs during this time period.