The correct answer is:
Leah deserves a second serve since her first serve was eventually called out.
From The Code, Item 30:
Since Leah’s opponent did not cause a delay between her first and second serve, Leah should only get a second serve. Since the time it took for her opponent to check the mark was likely similar to the amount of time it would take to clear a fault, Leah should be given one serve. However, if her opponent wants to be extra nice, she could offer Leah a chance to replay her first serve.
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