You are signing to be a full party to the contract.
The LL and any named "property manager" is a "first party".
Your DD and you become the "second party".
You will replace your child as the liable person if she and the LL fall into a dispute over the condition of the property and/or usage of the property and/or failure to pay rent.
If your clause does not have a time limit your liability remains for the full duration of your DDs contract.
So say in 20y time when she moves out the LL would expect to have the property back in the same condition it was handed over in with only normal wear and tear.
You say she is living alone but if she has the ability to modify the contract and add another you will be liable for the acts of that person too.
You should ask to be a notifiable person for correspondance so that you are not relying on DD to inform you of any problem.
Normal wear and tear is a subjective evaluation but you DDs aim is to hand the property (all of it) back in the same condition (or as near as possible as) it was in at the start of the contract.
Your DD needs to obtain a full list of contents and the first task is an inspection including to take multiple view point (dated) photos of the property and its contents.
Then inform the LL of any issues which may result in the inspection.
After that your DD needs to notify the LL of any issue which may cost the LL time and/or money as soon as she becomes aware of the issue eg mold / water leaking from pipes / etc
If DD caused the issue you/she will will have to pay the LL to a "make good" standard. That may be the full cost to replace with a new item or the be limited to the replacement cost of the original used item.
If you DD wants to make modifications (stick up artworks / new matress etc) DD needs to get the LLs permission in writing along with a confirmation of what the expectation is when the property is handed back.
AI explaination of Dilapidations:
Dilapidations refer to breaches of lease covenants regarding the repair, decoration, or reinstatement of a commercial property by a tenant. These items of disrepair or damage must usually be remedied or compensated for, with landlords serving a schedule of dilapidations during (interim) or at the end (terminal) of a lease.