This kind of sneak attack will amount to a full scale nuclear attack on Pakistan by India.
Lastly, are you aware that nuclear material can be traced back to the reactor which produced it in the first place?
https://today.tamu.edu/2016/02/04/n...r-tracing-illegal-nuclear-material-to-source/
What it means is, you will not be able to hide the fact that you used a nuclear weapon on Indian soil and, that what ever is left of Pakistan, after the nuclear attack by India, will be subjected to long term economic sanctions from almost all of the world. Lastly, it will destroy your CPEC projects including the new mega port that China is building and it is doubtful that China will help you any further as there will not be any benefit from that. India will be thrown 100 years back because of nuclear attack by Pakistan and Pakistan will be destroyed and with no hope of ever standing back.
There is another fun scenario however, given that these small nukes are to be deployed in forward positions, near the Indo-Pak border and they being tactical in nature, meaning the local commanders need to have authority to launch them so as to halt a Cold Start attempt by India makes them rather interesting. It means it is possible for irregulars to steal them and use where-ever they want. A really nightmare scenario. Imagine instead of that bomb blast in that hospital, it were a tactical nuke exploding. I wonder if this was one of the reason for US and USSR to withdraw these weapons.