Precision 3620 enable DVD-ROM reading and drive size

Good day,

Couple questions about Precision 3620 DVD-ROM drive. Unfortunately I got this read-only one.

I found a remark in Dell's manual saying that
"DVD-ROM drives may have write-capable hardware that has been disabled via firmware modifications"
I wonder if there's any way to re-enable it, then?? Sounds silly to sell a DVDR and just limit it by some firmware.
My model is HL-DT-STDVD-ROM_DH50N
Any ways?

Also, I am unsure about the drive size if I decide to buy a replacement. The manual says it's Slimline and 9.5 but the used 3620 drives do not look either slim or 9.5:
Replacement drive
Amazon 9.5 DVDR drive
Or do I need to buy a Dell's only drive, again? Hopefully not.

Thanks!!