Theory:

     “He’s clever,” said Grandfather. “Given time, I’m sure he could have tied the torn pieces of your blazer into a rope, and made his escape from the window!”
 
     His presence in the house still a secret, Toto was now transferred to a big cage in the servants’ quarters where a number of Grandfather’s pets lived very sociably together — a tortoise, a pair of rabbits, a tame squirrel and, for a while, my pet goat. But the monkey wouldn’t allow any of his companions to sleep at night; so Grandfather, who had to leave Dehra Dun next day to collect his pension in Saharanpur, decided to take him along.
Explanation:
 
The narrator's grandfather did not scold Toto or feel guilty for putting Toto in his place. Despite this, he praised the monkey's work and said, "He's clever". Furthermore, he said that if they had given more time to the monkey, it would have made a rope by attaching the torn pieces of the narrator's blazer and escaped through the window.
 
Even then, the narrator's grandfather said nothing about Toto's existence in their home. Toto had been moved into a large cage by the narrator's grandfather. The cage was in the servants’ quarters. It was in that cage where the grandfather's collection of pets lived.
 
Toto on a big cage.jpg
Toto inside the big cage
 
His collection includes a tortoise, two rabbits, a tame squirrel, and the narrator's pet goat. In the night, the mischievous monkey did not allow his fellow animals to sleep.
 
Since the monkey was disturbing the other animals, the narrator's grandfather did not allow Toto to remain in the pet's cage. On leaving Dehra Dun, he took Toto with him on his way to Saharanpur. He travels to Saharanpur to get his pension.
 
Meaning of difficult words:
 
S.No
Words
Meaning
1.
SociablyFriendly or agreeable
2.
PetAn animal or bird that you keep at home for pleasure
3.
Companion A person or animal that spends time with you
4.
Mischievous Behaving in a bad or annoying way though not intend to harm others
Reference:
National Council of Educational Research and Training (2006). Moments. The Adventures of Toto – Ruskin Bond (pp. 7-10). Published at the Publication Division by the Secretary, National Council of Educational Research and Training, Sri Aurobindo Marg, New Delhi.