1. The crux of your grievance is that your brother-in-law did not honour his promise of mutating in your and your husband's favour the house which, according to you, had been purchased by him by misappropriating the amount from Company A.
2. If misappropriation had taken place in UK he could not have been prosecuted in India. He had to be prosecuted under the laws existing in UK.
3. It also needs to be mentioned that the order which the court in UK may have passed in the criminal proceedings launched against him in UK could not bind the courts in India. The court in Gurgaon to which you have applied for injunction has to arrive at its own finding irrespective of the outcome of any criminal proceeding against your brother-in-law. However, this is surely a foregone remedy now as a dead person cannot be prosecuted.
4. After the demise of your brother-in-law his wife and children have succeeded to the property through natural succession. It is not clear to me as to what is the nature of injunction you have sought. You could not have sought any injunction against your sister-in-law in view of the fact that she is now the owner of the house.
5. The courts do not enforce oral promises. How will you prove that your deceased brother-in-law had promised to convey the title to you? Furthermore, even if it is proved that the property in Gurgaon was purchased through money that was stolen by your deceased brother-in-law from Company A which your father-in-law formed in UK, you cannot get the ownership of the property as it is a stolen property. Company A is at liberty to take out proceedings to recover the stolen money and also to attach the Gurgaon house which has been purchased from the money misappropriated from its accounts. A company has an identity distinct and separate from the persons who form it. These are the facets of your case which require a serious consideration. When judged in the backdrop of these facets, I am of the view that your action for injunction is misconceived in law.
6. Coming to the question of electricity, you cannot be given an electricity connection as you are residing in a property of which you are not the owner. You have to inevitably wait till the outcome of the decision of the court.
7. You have been residing in the property of your deceased brother-in-law despite not being its owner. The entire foundation of your stay in the house is an oral promise made by your brother-in-law. Legally speaking, your sister-in-law can launch criminal proceedings against you and your son in India for unauthorized occupation of the house now owned by her. It may also be mentioned that if the outcome of the injunction case is adverse to you, your sister-in-law may apply to and be granted by the court compensation against you.
8. Have a relook at your legal strategy, may be you will find a more efficacious legal remedy.