this is a practical applied policy paper that seems informative for donors considering their own charity decisionmaking

The Andreoni and Payne paper is about the government crowdout of private philanthropy (there are a bunch of papers about this), not about the reverse nor about crowding out among donors.

I might add a related issue -- decisions to give to one charity may crowd out other donations; the extent to which this is the case ('donations are substitutes') informs strategies for convincing people to give 'more effectively' vs 'give to effective causes.' See my notes: https://daaronr.github.io/ea_giving_barriers/chapters/substitution.html