If I understand right, the carpet is around two plus years old. (Widow/1 year...tenant 1year...tenant renewal 3 months) You can only charge for the remaining life of the carpet (7 years or 10 years depending on how you do your taxes)
You might consider requiring the tenants to pay for the estimated cost of the carpet (unauthourized removal) with the understanding that replacement carpet will not be installed. (tenants will damage carpet over next 9 months). If the tenants pay, let the lease ride out and non renew. Deduct the replacement cost of the damaged sections from the security deposit and sue for any amount not covered.
Or, enter into a written agreement that tenant can pay the damage cost over the next 8 months. (Divide total cost to replace damage area by eight to arrive at monthly amount)( make this one month short of the time remainging in the lease). State that the monthly amount due is additional rent so if the tenants fail to pay, you can evict for non payment. Do eight months and non renew the lease.
Or, you can proceed to issue a 'Seven Day Notice of Noncompliance with Opportunity to Cure' and proceed to eviction if tenants do not comply.