This is mostly an issue being caused by IGIXML, but as far as I can tell there is no way to fix it on their end without removing the ability to use images & etc that the mod has. According to Lunatrius/InGame-Info-XML#71 , at least.
With that being said, is there a possibility of a workaround for this case (and other mods that use the font renderer in the same way)?

this part from the SelectedItemHandler file seems relevant to me:
(https://github.com/Fuzss/consoleexperience/blob/1.12/src/main/java/com/fuzs/consolehud/handler/SelectedItemHandler.java)
String text = this.tooltipCache.get(i); this.getFontRenderer().drawStringWithShadow(text, (float) (posX - this.getFontRenderer().getStringWidth(text) / 2), (float) posY, 16777215 + (alpha << 24)); posY += i == 0 ? 12 : 10;

Or is this not fixable because you need tooltips to be center-aligned and not left-right aligned?