People often don't realize that if you fly through US airspace after violating certain US laws as non-citizens, you will be apprehended through an emergency layover coordinated with the carrier. That's a contributor to why US federal three letter agencies constantly ingest passenger manifests.
After which terror charges were never filed and the gov't began seeking deportation on extraordinarily pedestrian grounds, with his lawyer speaking publicly about the case:
Can't find anything after that, but he's not listed in the USCIS's Online Detainee Locator System and AFAIK could not have been legally deported to Somalia.
WikiLeaks documents on him, combined with other sources, paint a picture that he's either a) a somewhat prolific terrorist/human trafficker; or b) a politically active Muslim immigrant in the USA who might be kinda sorta guilty of some clerical crimes and may've acted a teensy bit dodgy when returning to the USA. (b) is probably way more likely given that DHS was apparently OK releasing him on parole.