Ok, found the solution! I was treating all things in the modulator as data exportable by exportState(), but that one does not export or include table data, regardless of the modulator, it seems. So this one is the appending solution of for the table data of the "Global Static Time Variant Modulator", that has both buttons and table data:
Content.makeFrontInterface(633, 400);
// Prepping for export, original modulator
const var Modulator1 = Synth.getModulator("Global Static Time Variant Modulator1");
const var mod1Table = Modulator1.asTableProcessor(); // asTableProcessor, was the missing piece.
// Export the table (only one so index is 0)
const var export1 = mod1Table.exportAsBase64(0);
Console.print("export1: " + export1);
// Prepping for import, next modulator
const var Modulator3 = Synth.getModulator("modulator3");
const var mod3Table = Modulator3.asTableProcessor();
// Use the previous export1 as the data input for table index 0.
mod3Table.restoreFromBase64(0, export1);