"A Gomez Lyd has various suppliers from markets accross the world all of which are visited and assessed for suitability of supply. This includes ethical surveillance" - this indicates to me that A Gomez are not only visiting the suppliers for suitability of supply, but they are also visiting them to see the working conditions are fit for workers, health and safety etc.
"We work with some countries which are higher risk concerning modern slavery and staff welfare. The are carefully monitored and visited regularly" A Gomez recognise that modern slave labour does occur in some countries, instead of avoiding to supply from these countries, they actually work with them and check regularly to avoid slave labour happening.
They also implement a policy for each of their suppliers, they "conduct due diligence on all suppliers before allowing them to become a preferred supplier" they have polices in place such as termination of any suppliers if they suspect any modern slavery instances, they ensure the employees of their suppliers are paid legal minimum wage.