Any dump online can work or not, the image can have another system ids, mac, etc…
from Dell and only your dump has your original data.
No regular flash or just FPT the ME region usually works, since you have now full permission on read/write full spi regions, better to follow forum guide and re-initialize the CSME engine, then write back full spi.
EDIT:
Well sir… if you don’t, get it or get an SPI IC programmer, that’s all, good luck.