This site states this specific instruction directly, closing its own transparent-label section: if this information is difficult to find on the packaging or official checkout page, treat that as a reason for caution.
Worth reading "treat that as a reason for caution" as a direct behavioral instruction — this site is telling you what to do with the finding, not just noting that the information might be missing.
Worth noting this site applies this exact standard to SodaPeak itself — its own inability to find a complete ingredient list is treated throughout this site as a genuine reason for the caution it repeats across multiple sections.