It takes the most experienced fast jet engine developers many years to develop a new engine. I think the example of the M-88 timeline was given earlier in the thread.Why not, please substantiate your claims. Is there a prerequisite by law to have spent a certain amount of time developing an engine or what? You can do anything in that time when you make the best use of time.
I don't think it is a matter of substantiating why the TF35K will take many years to develop but more a matter of substantiating how it could be developed and tested in less than 5 years, given its current status. Has it even been designed yet? I have not heard that so I presume it has not.
Yes. there could be great urgency given to the TF35K development programme but there will be problems to overcome, problems that I guess will be more difficult to remedy for an inexperienced developer than for an experienced one.