Without having done extensive research regarding the relevant state and national statutes in India, given that India's legal system is derived from British common law and that British common law jurisdictions would be uniform in how this question is resolved in a matter that arises from the common law, I think I can provide an answer that is likely to be correct.
The answer is that once the business owners and officers "delegate responsibility of their office premises to a freelancer" that person is no longer just a freelancer, that person is now also an agent of the business.
In most kinds of businesses, it is legal to delegate power to run a business to a third party agent. But, there are exceptions in regulated industries. For example, a pharmacist could probably not legally delegate responsibility for a pharmacy to someone not recognized in the pharmacy's license as an authorized manager of the pharmacy. Software development would not normally be subject to this kind of regulation unless the software involved matters of national security (e.g. software for missile navigation pursuant to a contact with the military).
What if somebody steals equipment while the bosses are away?
What if somebody has a serious health condition?
What if there is a fire?
...add any number of unexpected situations.
Once the freelancer becomes an agent of the business, the freelancer owes a fiduciary duty of care, a fiduciary duty of loyalty, and a fiduciary duty to account to the business, and has liability to the business only if those duties are breached.
None of the examples suggested involve a violation of a duty of loyalty (which would involve, for example, offering a business idea of the business to a competitor).
A duty of care would be breached if the freelancer acted negligently or carelessly and that was what caused the harm. If the left happened because the freelancer failed to lock up at closing time, the serious health condition was duty to a failure to be careful to maintain safety precautions in their absence, or the fire was due to the freelancer smoking near petrol storage areas, the freelancer would probably have liability. But, if these mishaps occurred despite the freelancer exercise the same level of care that the regular managers of the business exercised when they were present, the freelancer would probably not have liability for the harms.
With regard to stealing equipment, this could also implicate the duty of a fiduciary to account. This duty says that the agent has a duty to keep track of what is received from others and what is spent, and if those records don't correspond to the reality when the business owners return, that the agent must make up the difference unless he can explain it. In this situation, loss of equipment would rarely constitute a breach of a duty to account, while a failure of the petty cash drawer to match the record of receipts and disbursements probably would violate the duty to account and require the agent to make up the difference without regard to actual fault or personal benefit.
