ATX/EATX may not fit right. It looks to be SSI-EEB which shares some but not all of the ATX standoffs (and the middle line just don't look like they're in the right place even for that). Holes in the MB tray for ATX may not be present. Feel like drilling? Additional challenge is that the top expansion slot (next to the I/O plate) is not present in the case, so if your board has a top PCIe slot and you need to use it, you won't be able to install any card with external ports or big enough to require the slot bracket for retention.
The stock PSU is listed as ATX/EPS12V standard, so that shouldn't be an issue. Look for a unique connector from the PSU (narrow with white wires) and see if it goes to the motherboard. I don't see a place for one on the stock mainboard, but some redundant systems require communication with the MB to function.