are you in the city limits ?
how close is your nearest neighbor?
is there a "no burn" in effect in your county?
yes, the way my neighbor does it is to put a big of charcoal on it and burn it out.
couple of lawn chairs, some cold brew, hot dogs for the kids, that'll work right there.
The object is add fuel TO the stump, don't use the stump as fuel.
Pouring accelerant onto it over and over is just wasting your fuel and time.
slow HOT burn will do the trick nicely. If you have a big steel ring or half of a steel 55 gl drum
to make a fire ring, that will contain your fire as well as add the ambiance to the cookout.
True story:
when I was a kid, (1960) my dad was helping his uncle blast some stumps with dynamite
after a storm knocked down some big trees.
There was this huge black walnut stump that they first tried with the tractor.
then, 1/4 stick of dynamite - didn't budge it..
another 1/4 stick - bunch of smoke and some dirt. same result.
we went way back into the field, full stick of dynamite - - -
BOOM !!! the core of that stump went straight up, and up, and up and up - - -
then, came down, and down and down and down - - -
like in slow motion - landed on the front porch roof.
Granny came running out raising hell and screaming.
funniest thing I have ever seen since then !!!
But, could have been a totally different devastating day if it had been 15-20 feet over into the house.
but yes, get the green wood hot enough with the charcoal and it will burn right out.
It may take a couple of evenings, but, it can be a fun family time also.