If I recall correctly, in terms of fidelity to the original in our use, the most often having problems was an inserted spreadsheet, better but still with occasional problems (especially when resized a fair amount) was a copy and pasted one and the best was a pdf version added to a map pdf, either as a stamp or copy and paste. If you can't go the pdf route, you might see if resizing your sheet in Excel and then copying and pasting it with little or no resizing thereafter works better.