Tamborine Tiger has a legally served eviction notice she has to move out. If she stays as you say she will be forcefully evicted by baliffs. The in-laws have housed her free for 15 years , there is no way they are being dishonest by wanting the house back it is their house I would imagine they want their son , Tigers ex husband to have it.
Tiger has no tenancy agreement so she can't pay rent .
If Tiger has £16,000 (actually I think the sum mentioned was £13,000) then she has to use it as a deposit to get a private rented house.
You are giving her false hope where there is none.