From what I understand the rules for Texas differs from that of other states. Texas requires that you pass NAPLEX/MJPE within 3 months of obtaining FPGEC before you can get an intern license. In a case where one gets the intern license and starts internship immediately after getting FPGEC (you can do that if you show proof of NAPLEX/MJPE registration within 3 months of FPGEC), you would still be required to pass NAPLEX/MJPE within 3 months or stop internship.
In your case you can still get the Texas intern license, you just need to pass NAPLEX/MJPE exams first before you apply
Hope this helps!!