Hi. Having all those other concurrent illnesses (hypothyroidism, congestive heart failure, kidney disease and diabetes) increases the risk that your mom will have some medical complication during or after surgery. Should she proceed with it then? The final decision is still up to her. As long as these other illnesses can be stabilized, and as long as the hospital where the surgery will be done can provide the necessary critical care support, then you can probably push through with it.
I can't give you a medical opinion. What I can say is that you have to trust your mother's medical team with all this going on.
Prayers and best wishes...