Hi Don,
Table parameters of external processes must be specified as plain arrays, not as structured objects. For your example this should work:
for ( let i = 0; i < bias_filelist.length; ++i )
biasII.images.push( [true, bias_filelist[i].path, "", ""] );
although this is much more efficient:
let images = [];
for ( let i = 0; i < bias_filelist.length; ++i )
images.push( [true, bias_filelist[i].path, "", ""] );
biasII.images = images;
In this example I assume that your bias_filelist is an array of objects, each of which has a path property of String type.
A useful trick is clicking the Edit Instance Source Code tool button on a tool's interface (blue empty square button). This opens a code editor window where you can edit the JavaScript representation of the tool's current process instance. Here you can copy fragments of code and inspect it to learn how parameters have to be specified in your scripts.
Let me know if it works.