Witness not turning up

Dear Sir, My Dad (landlord of cess building) is charged under section IPC 337 & 427 by police when one of our tenant complained against him. The complaint is that my Dad did not repair and did not allow MHADA to repair the building and as a result a wooden log fell on tenant's son injuring him. FIR was filled in 2013 and court proceedings started in 2014. Our lawyer has cross-examined a couple of witnesses including the tenant and we have found several evidences during cross-examination which contradicts the date of incident and injury. This complaint was maliciously filled against my Dad to coerce him to sell the property to a builder who wants to club our property under cluster re-development. As it looks certain that the complaint wont stand the law, the witnesses are intentionally not appearing before the court for cross-examination for last 6 dates (approximately 10 months) everytime giving strange reasons like attending marriage, attending exams, attending coaching class, etc... As the tenants and ourselves stay in same premises we clearly see them at the building but they submit false reasons in front of court just to prolong the proceedings. Are there any remedies under law for us against this?