有眼無珠 Eyes Without Pupils
那些妖聞此言，魂飛魄散，就在水中跪拜道：「望老爺方便方便！我等有眼無珠，誤捉了你師父，雖然吊在那裡，不曾敢加刑受苦。望慈悲饒了我的性命，情願貼些盤費，送你師父往西天去也。」那些妖闻此言，魂飞魄散，就在水中跪拜道：「望老爷方便方便！我等有眼无珠，误捉了你师父，虽然吊在那里，不曾敢加刑受苦。望慈悲饶了我的性命，情愿贴些盘费，送你师父往西天去也。」
逐句解 Line by line
The demons heard this and their souls scattered in terror. There in the water they knelt and bowed: "We beg your lordship to be merciful, be merciful!"
散 is sàn, to scatter. 魂飛魄散 sends both kinds of soul flying — the 魂 that goes up and the 魄 that stays with the body. 方便 is a Buddhist word: expedient means, and by extension an accommodation, a kindness done.
"We have eyes without pupils in them. We took your master by mistake, and though we hung him up in there, we never dared put him to torture or make him suffer."
有眼無珠 — eyes but no pupils — is a set phrase for failing to recognise somebody important, still in daily use. 不曾 takes céng, the aspect word: never once did.
"We beg you in mercy to spare our lives. We will gladly put up something toward your travelling costs and see your master on his way to the Western Heaven."
盤費 is travel money, expenses for the road. They are offering to pay the pilgrimage's costs — which is, precisely, the almsgiving they lectured Tripitaka about at the table.
They surrender, and every phrase of it is correct. Eyes without pupils, we took him by mistake, we never tortured him, we will pay your expenses.
The last offer is the one to sit with. They propose to fund the pilgrimage and see the master safely west — which is exactly the act of almsgiving they were lecturing him about when he refused their food. They know the forms perfectly and they always have.
It is also worth noticing that their factual claim is true. They did hang him up and they did not hurt him. What they were going to do was steam him, and that is not torture, it is dinner.