You could have said you were busy that day to either of them. For the 2nd one you even could have hired another sales guy and you wouldn't have even been in that situation.
But you didn't.
And in the end, this guy's got a time tracking/invoicing app he sells to small businesses, his scenario is completely different. I don't want to be too dismissive, but it seems more suited for the Amy Hoy/patio11 route rather than the YC one, it's not a pants on fire, runaway scaling startup.