hdfc ergo health claim

Hi, I have taken a health insurance from hdfc  ergo optima secure for my father 1 month back age 57. He didn't have any surgery nor diabetic in his life. He is experienced chest pain 2 weeks back for 2-3 days and no chest pain after that. He had a chest pain even 1-3 months back but mild. We thought it might be some gastric. We are planning for a hospital visit after a week (it becomes 35 days after purchasing policy), if he diagonesed with any heart condition and any surgery has to be done like angioplasty. Will hdfc approve this claim since it doesn't come slow growing disease or pre exisiting disease (Since I never had surgery or diagnosed or been to  hospital). My relative recently got angioplast done in Bangalore which some 4 lac. I am worried about that fee if he is diagonesed with any such thing. I wanted to know so that I can prepare for something. My doubt is also whether they will add any loading charges if go for claim next week saying it's heart condition that you didn't disclose (he didn't had any surgey or diagnosed with any thing, i didn't disclsose anything)? Whtat are my options? I don't have corporate policy and not eligible for pmjay?