Like to post the outcome. After deliberation with his research professors, he found his interest and decided to remain at U of I as 5th year MS program. He is also doing thesis along with it. By doing this it saved him a year from a typical 2 years MS+thesis program at any other universities, therefore he didn’t apply out. Who knows a year from now, may be we are talking PhD options based on how the research goes next year and his interests evolves around it.
On a side note, he had also received a FT offer at FAANG and become hard to choose between pursue graduate program or accept offer. But he decided to continue graduate program.
Thanks for everyone to chime in and guide us.