I am not sure that. Because;
1) From asus site the i5 4690K is not in the cpu support list, but I think it is the mistake because the i7 4790K is in the list. http://www.asus.com/us/Motherboards/Z97P/HelpDesk_CPU/
2) From the list I guess the i5 4690k need the same BIOS version ( 0310) that is as same as for the i7 4790K.
3) The BIOS 0310 was out 5/30/2014, so it depends on the MB, if the ASUS make the MB after that day you should be fine, and you can check the serial numbers ( you can buy from the local store only) to confirm the date is manufactured, like year and month. Here is how to
http://www.service.asus.com/#!motherboard-serial/cqt6
In the Product Registration section, then How do I locate my ASUS product Serial Number?
From the asus: ASUS products have serial numbers that are 10 - 15 characters in length in the following format:
1st digit: Year Manufactured (last digit of the year)
2nd digit: Month Manufactured (1-9, A-C)
4) Keep in mind your MB can't use the USB BIOS flashback feature. That means if the MB need update the BIOS you need other cpu to do it.