Join Date:Joined: Mar 2011
Donate to Me
Is there a reason you don't buy a card? A top-notch 32 GB SanDisk, UHS-1/Class 10 card is only $25 and smaller ones even less.
Odin doesn't know squat about MTD, just the OEM partitions, so you're probably out of luck looking for a simple solution down that path.
You might be able to flash just the kernel with heimdall, then boot into recovery, manually remount /data onto /sdcard, adb push the ROM, and install it with the flashed recovery.