Okay, I've been trying many things with this \startpostponing code--if I understand what's happening, its moving the figures to a later page. I'm not sure that's quite ideal, its not fully working with my actual documents, and leaves lots of empty white space, when I'm already in a situation where I need to reduce page count.
So I thought an alternative route:
(1) have a code that checks "what is current footnote number?" that sets that as a variable
\def\currentfoodnote{\somevariableincontextthatgetsfoodnotenumber}
(2) adjust my placefigure macro such that the footnote is outside the placefigure, but color it white so its invisible:
\define\showafigure{
\cite[author2019]<--somehow hide this invisible
\placefigure{Caption\superscript{\currentfootnote}}}{\externalfigure[cow][width=\textwidth]} <--this places a superscript number inside the caption, but it isn't the true marker(3) in the caption, place a superscript number with value to
\currentfootnote
Its basically a fake footnote, just a superscript number of the same value as the real footnote.
Shouldn't this result work? Any idea how I can get current footnote value?
--Joel