Gamecube controller wont help you as you removed IOS70. Recovery menu requires a functional System IOS (in your case IOS70) to run.
No there is no app you can just put on your SD card, if there were I'd have mentioned it.
The Wii was never designed with people like us in mind and the ability the read off SD cards without a system was never built into the Wii's hardware. With bootmii/boot2 they found a way to give us this but of course most people can't install this, yourself probably included. If your Wii was purchased before Aug 2008 then you have a chance to flash a working bootmii/boot2 to the NAND and will be able to recover. With a post Aug 2008 and no NAND backup then you have no hope, none at all, zip, zilch, nada.
Not really doing much Wii stuff these days.
and if i use a modchip? is there any that works? like savemii? T_T