My understanding is (and I went to quite a good session at Philly Trans health on this last year) is that the complications are not later, necessarily, but right at the time of surgery (or a few months later say).
Common complications are strictures (tightness) and fistulas (which are small holes), and lack of complete closures so you have leaking. And these are common, in that it doesn't matter how skilled, all surgeons have had cases. Some of these self-correct, and others require going in and patching up, essentially.
Another problem, with metas (not phallos) is some guys end up too small to actually stand to pee, while some stand to pee with difficulty (i.e they could go in a stall perhaps). I have heard of infections (though not like your friend, I think this is uncommon) and failures to connect completely, but not death, I mean at this time.
Some surgeons are able to go in after a phallo or meta and do these. Someone like Dr Crane in CA (or maybe he's in Austin now) would likely be able to do this as he was trained as a urologist and has done a lot of repairs on young cis males. (Some percentage are not able to STP). I believe after the surgery might be harder with a phallo than a meta (though I don't know this).
Actually I have heard of guys having fewer UTIs after hookup. The reason is that the length adds distance from the anus, which is a reason that female bodied people have more UTIs.
OTOH, the most common reason that guys do NOT get hookups is for concern re: the amoutn of complications. I can't lie and say it isn't fairly high, even if most are correctable. It's a tricky procedure, basically going in and making a urethra lengthener and threading inside the shaft and suturing it all completely closed.
--Jay