How can one have absolute trust in an IVF doctor, and what if their dishonesty becomes apparent later? How does that affect the parents' view of the child born through their hands, and what is the child's sin in that? What is the ruling of Islamic law concerning this child, and how should they be dealt with Islamically?

The doctor must be trustworthy, God-fearing, committed to His law, and possess sufficient experience. The procedure should only be performed when absolutely necessary and after taking the required precautions. If the procedure is carried out according to its legitimate Islamic guidelines, there is no need to worry, as the default is safety from deceit. As for the child, he is blameless and should not be informed of what happened to avoid distress that might affect his behavior.