NOC of the coowner and validity of L&L agreement

My company signed the L&L agreement with the commercial property owner who is not the sole owner of the property. Unfortunately, we discovered this fact on the day of signing L&L agreement. We got a commitment from this owner that the needful NOC will be furnished to us in the date of possession. The coowner acted reluctantly even after taking followup for two months. So the company decided to give him ultimatum and asked him to produce NOC and POA from the coowner in 15 days failing which the company would vacate the property in a month and the L&L agreement terms will not be applicable to the company, as the L&L agreement is a legally invalid. Despite of this ultimatum, the coowner responded as the company would have asked for NOC before signing the agreement. Based on his response, the company decided to serve final notice and decided to vacate office thereby declaring that the rent would be adjusted against the deposit amount and that the company is not liable to obey any T&C stated in the L&L. After this final notice, the coowner introduced himself and emailed the NOC and also warned the company to stick to the T&C in the agreement and would serve us legal notice. The company decided not to change its stand sin e the decision is already taken. Pl let me know if the stand taken by the company would be legally valid? Thanks