Rowan was not exaggerating his present condition. Primordial Demon had accurately pointed out the time of his death, and he had to work with what he had.
He could barely investigate this strange and new party he had come across or find another route for escape, not when he was this close to death.
This was the reason he had missed obvious social cues and appeared rude to his hosts. Rowan was focusing everything he had to keep the New Light safe, and that meant dealing with the obvious loopholes inside this castle.
He was a Supreme Creator and a Crafter, able to create both flesh and stone, and all the mysteries of Reality up to a point were open to him.
He had been causing a lot of destruction these past few moments, killing hundreds of billions of Celestials and Thrones of Primordials, causing his understanding of destruction and the act of taking lives to multiply exponentially.