Do as you wish, but I have more luck with freeze plug sealing than I do with pipe plugs. Think about the 15 psi the block sees in the coolant jacket and you never see a coolant leak from properly installed freeze plugs. They're also used at the front of the oil gallery where they see as much as 70 psi and you don't see them leaking.
The dipstick hole is 12" above the oil level, isn't pressurized, and never sees oil. Do as you wish, but I wouldn't risk metal shavings in the pan, nor would I permanently ruin that hole as a disptick position.