The Contractor is correct unfortunately.
Clause 81.1 says that all the risks that are not the Employer's or the Contractor's are yours. The Employer's and Contractor's risks are listed at 80.1 and none of those are for loss or damage to your works during the course of the works.
In additional clause 84.2 states that loss or damage to the subcontract works is a matter for insurance taken out by you.
If it is something that becomes out of control you could claim the contractor is in breach of an implied term to manage its subcontractors which could potentially be a compensation event under 60.1(18) and if the Contract says it is out of his control then it could be a compensation event under 60.1(19), but in either case it is only if the damage is significantly more prevalent than would be reasonable.
Clause 81.1 says that all the risks that are not the Employer's or the Contractor's are yours. The Employer's and Contractor's risks are listed at 80.1 and none of those are for loss or damage to your works during the course of the works.
In additional clause 84.2 states that loss or damage to the subcontract works is a matter for insurance taken out by you.
If it is something that becomes out of control you could claim the contractor is in breach of an implied term to manage its subcontractors which could potentially be a compensation event under 60.1(18) and if the Contract says it is out of his control then it could be a compensation event under 60.1(19), but in either case it is only if the damage is significantly more prevalent than would be reasonable.