Hello Robert Fairchild,
Welcome to Microsoft Q&A forum.
As long as you have transferred all of your important files to your new computer, wiping the old computer shouldn't affect anything in your new computer. The 2 computers work independently and data changes in one of them will not affect the other. PIN and BitLocker key is also device specific, so it shouldn't be affected by a wipe on another computer.
If anything, I would suggest you check whether you have fully backup your data and whether your Windows license is transferrable, but I'd also assume that your new computer have its own license.
I hope this clarifies.