I am not sure if there's a more elegant way but you could make a text field on the site authorization record which combined the provider name with the authorization date. Then float up that combine text field up to the Sites table, then look it up back down to events. The event knows the provider and then you would have a formula that would purse out the possible authorization date provider combinations to find the one that had the right provider and turn that text format a date back into a real date field.
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Mark Shnier (YQC)
Quick Base Solution Provider
Your Quick Base Coach
http://QuickBaseCoach.commark.shnier@gmail.com
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