وَقَدْ يُحْذَفُ الْعَامِلُ؛ لِقِيَامِ قَرِينَةٍ، كَمَا تَقُولُ لِلْمُسَافِرِ: «سَالِمًا غَانِمًا» أَيْ تَرْجِعُ سَالِمًا غَانِمًا.
Translation: The governor may be omitted when context makes it clear. To a traveler one says “Safe and successful!” meaning “May you return safe and successful.”
The book explicitly supplies tarjiʿu as the implied verb, which explains the accusative on sāliman and ghāniman.