It was an eerie exchange that resurfaced several scenes later, when, approaching the precipice of death, Theresa heard Ford reference the same cryptic phrase: the board tests "me every now and then -- I think they enjoy the sport of it. This time, they sent you. Sadly, in order to restore things, the situation demands a blood sacrifice."
Was Theresa the blood sacrifice all along? The answer can only be yes if Charlotte is in cahoots with Ford. And that's a twist I hope we don't encounter, as it would suck all the fun out of the creative director's antagonistic relationship with the board, and it would ooze cheese like stuffed crust pizza.
A more hopeful reading: Theresa is Ford's sacrifice, but not Charlotte's (hers would be the newly lobotomized Clementine, or worse, potentially a park-goer). Ford likely echoed the phrase to assert his power, showing Theresa that he overheard her conversation with Charlotte (via Hector) and that he's privy to the board's plans of a coup. For Ford, Theresa had to die so he could protect his hold on the park, and so he could flex his muscles at his enemies, the pesky moneymen.