I blew insulation inside the house and also found some roof areas that were leaking a small bit.

The reason the shower is being replaced is because they notified me of a water leak coming from the shower.

Inspectors will check for leaks, sagging, or missing shingles, particularly in older homes.

Few more points:Their lease is valid till May 2025.This is the first time she even told me about mold.In the email she did ask me to settle the lease.I have a little less than a month of rent as security deposit, which I am ready to settle without any additional penalties for abandoning the property.At this point I am okay with her leaving the place, just I want to get the control of the property back to fix the mold issue.History:1) Recently the AC has been replaced and after that there was some intermittent issue with the installation (temp doesn’t reach target intermittently) and I had to call the tech back 5 times to finally get it resolved.2) Also last month I replaced electric range with Brand new Electric range.3) Two months back she said the refrigerator was leaking, I asked her to send picture of the make and mode of the refrigerator, but I never got a reply back.4) Also for last 4-5 months she has been asking me to send her 5-day notice so that she can claim reimbursement, I was sharing a document and she was paying the rent a little late.

i.e property can't be rented with a leaking roof.  

If there is a leak I look at it.

Recently, we had a leak from the A/C in the attic.

Landlord Response:  Not my problem, lease says you pay everything.Roof leak:  Tenant says your responsible.   

Is the roof leaking to a point where its life is over and a new roof needed?  

Most utility water meters have a small red or black dial on the face of them that is a leak detector.