This isn't exactly a buyer's market, you know. Avoiding errors (which, really is no big deal, as to err is human) and double checking ANYTHING is the mantra (re: motto) of this hobby.
3) Caveat emptor, man. Is should have been clear from the specs and screenshots on the site you bought it from that there was no 25pin m/f extention cable included.
Caveat emptor means "buyer beware"