ReadyNAS NV+ v2 Only Enters Normal Mode Cant Get Into OS Install mode

Just as a note: OS reinstall does not fix everything that may be broken on the OS. OS reinstall reapplies the firmware from the chassis onto the operating system RAID on your disks... it does not really attempt to repair broken configuration files or databases that may have an issue. It does reset the admin password back to default (password or netgear1, depending on platform) and attempt to reset your network adapters back to a default state (DHCP and enabled). 

In your case, if your issue was the UI showing as offline like it was, that issue is probably not going to be easily resolved by performing an OS reinstall. Intervention on a tech support level is typically required, whether it is you performing the fix operation or a support expert.  There's likely an issue reading a config file somewhere (ext is prone to file system corruption relatively easily), or the database which caches information to show you in the UI is down. 

Usually the best course of action is to boot the unit normally and then see if you can access your data using a network protocol (even though the web interface is not working). If you can, backup all data you can... then factory default. Then check the status of the disks to make sure they are okay... because it will create new healthy file systems and you want to restore data to healthy disks and continue on.  If you cannot access your data, you might have bad disks in the system at which point you may not have data to recover and would need to buy new disks and perform a factory default.