No way you stripped it, get a strong light and lay down, look up.
It is odd.
The bolt carries no washer and is an Allen head if i remember correctly.
Start it with your fingers, then snug it.
Fill the new filter with oil and tighten it in place.
I hate the little one even worse.
'02 KTM 640 Adventure-lowered
"On the road there are no special cases."
Cormack McCarthy-The Crossing
The faster it goes the faster it breaks.
And high performance=high maintenance.