Unfortunately, the authenticity of the video can not be objectively verified at the current time.
A video surfaced on September 20, claiming that PLA soldiers crying as they were allegedly deployed to the border. It went viral on social media, with several commentators appearing to mock the Chinese troops. This was first posted by a Pakistani comedian which was later picked up by a Chinese national.
Taiwan News reported that the new troops were reportedly college students, and five of them had proactively volunteered to serve in Tibet. The video was filmed at the Fuyang Railway Station as they prepared to head to a military camp in Hebei Province.
Apart from the claims made by the Taiwanese media, there are no credible reports to confirm whether these soldiers were crying as they left for the Indo-Sino border, or whether they were just being emotional leaving home. Since Taiwan is in a standoff with China to secure its independence, we cannot solely rely on the reports coming out of Taiwan. Thus, this claim cannot be objectively verified at the current time.