I thought about something, what if we combine an onda rom which doesn't have a working Wifi/Camera but a working touchscreen (like V812Core4-V1_v2.0); with the original stock rom of this tablet (Allview2_M809Q5_20130903) ? Then we will finally have a good rom that is working on our Allview 2 speed quad.
So, as far as I watched tutorials, to have this custom rom of ours we will need to extract the softwares img files (both V812Core4-V1_v2.0.img and Allview2_M809Q5_20130903.img) into 2 folders (each one that will contain the System.img, Boot.img, Recovery.img ..etc); then we should replace the boot.img from the stock software (the folder obtained from Allview2_M809Q5_20130903.img) into the Onda's software (the folder from V812Core4-V1_v2.0.img); aaand then repack our Onda's modified software (or, let's say Our custom rom) into a new img that will be flashed with Phoenix.
The Boot.img that will be replaced contains the Wifi "drivers", so in this case the Wifi will work (I think...).
Also there are tutorials on youtube on how to do that. (eg "[HOW-TO] Create, Unpack and Repack update.img ROM on Windows ").
Now I just need an expert on android to tell me if what I said is possible... or... we will remain with our stock, laggy, disastrous firmware/rom from Allview.