first of all, you have posted FDM issue in Essbase forum. Thats the reason you didn't get replies to this issue.
To resolve this, we need to Oracle Client 32 bit first then Oracle Client 64 bit.
Install Oracle Clients completly. (As per documentation, we need to install Clients completly. Means choose Administrator, not instant client and custom)
After installing also if get same error, Goto Environment variables, Edit PATH variable and copy the 32 bit Client path to the first in the PATH variable.
Then reboot the Server and try again to create FDM application.