I am in Scotland and have been shielding, so no childminding for me during the pandemic.
However, I have been advised to still take extra precautions, as although doubly vaccinated, being immunosuppressed has meant, that for me, the vaccine is not fully effective.
I can appreciate that your DIL must be anxious about not having a childminder, but she doesn't seem to be too concerned about you and your husband's welfare. My son and DIL have decided that it is still too risky for me to childmind and have made alternative arrangements.
I feel for you, being torn in two.