ReSourcePro Operational Solution Private Limited

This company conducted 4 rounds of interviews and offered me 95% Hike where there is no discussion of negotiation at all. They directly confirmed the offer and that raised a red flag in my mind(Am I being too skeptical here? Instead of accepting it).

And while discussing the compensation details they asked me to enroll in a third party Skill Development program(Tech Minds) to complete Microsoft ASP.NET Professional Certification (Core/MVC) within 15 days and the certification costs around 20k and they informed upto 25k any skill program will be reimbursed in your first salary.

I have asked them to share the offer letter, initially they hesitated but they shared it with me. I have asked them for a 60 Days time to join the org and they agreed for that as well.

Is there anyone in the same org who can give me some assurance to accept this offer or not.

In my head I'm thinking the worst case would be I'll be losing 20k(which is a big deal for me) and the best would be either I can join this org or I can show this OL and continue attempting for the interviews.