Dong Tianyu did indeed possess a sizable amount of supplies, but the vast majority of these were inanimate goods stored in his Shadow Warehouse, as the initial size of his Cave Mansion was quite small, resulting in him not preparing many living items.
By the time Dong Tianyu upgraded and expanded his Cave Mansion, the Catastrophe had already descended and the usual living things from before the Catastrophe were no longer available outside.
Although the temperature didn't plummet instantly during the initial Cold Catastrophe, the external temperature was changing every day. Most people were in a state of confusion and rapidly moving to underground shelter centers.
Apart from Officials, very few people brought living creatures to the underground shelters. Even if some did, they would kill them to fill their stomachs during the period of food shortage.
