I have a few friends from Rajasthan Technical University and according to them, it’s not likely that you will be able to get your original certificate directly from RTU Kota. It is supposed to be distributed by the college only.
So check with your college. If yours didn’t reach the college, then let them send a request to the RTU Kota office for the same and wait until then.
If it's urgent you can visit RTU Kota. Don’t forget to bring your original documents like provisional degree, consolidated marksheet, semester-wise marksheet, registration card, identity card, etc. You can also contact the number provided on the website. Although they hardly answer.