Indesign does not have an export JPEG preset, consistent exports would rely on setting every option consistently. Is "Anti-alias" turned off for this particular export?
Does a different computer render the same results?
Does problem computer have the font loaded?
Does problem font have any faux styling?
Is text placed over transparent elements?
If you were to export to PDF, rasterize PDF in Photoshop at same rez, does this look better than ID jpeg export?