Opinions are not facts. The test reports of NS are facts, the report of the doctor is just his opinion, which cannot be legally termed as falsifying. Though, it is, quite arbitrary.
However, the doctor seems to be a specialist in making these type of reports. He has given many spins to the story.... Patient suffering from many diseases and conditions all at once, therefore a multidisciplinary approach is required. Note that the doctor is just a cardiologist. So, he has deliberately moved towards an area, where things should get complicated or at least appear to look complicated. Then he has concluded that due to COVID restrictions, he will not advise his patient to board an airplane. Again note that there is nothing about his health for being so frail that he cannot take an aerial journey.
Lastly, he has also brought about the COVID-19 crisis as an excuse for delaying the cardiovascular tests and procedures. So he is not taking any liability for his own specialty i.e. Cardiology. He has just written about the general health condition of NS and has expressed his concerns in the areas where he is not specialized. Also, to serve the objectives of his client, he has stressed on COVID-19, as being a barrier for not carrying out his job on the patient.