The road wasn't blocked since we see other vehicles drive around her, which ICE could have done instead of escalating the situation as we see them doing in dozens of videos coming out of the Minneapolis area. Keep in mind that the administration is not acting in good faith. Trump has politicized ICE to go after blue cities he doesn't like. Stephen Miller started the escalations when he sent ICE to Home Depot parking lots in LA because his desired quoata wasn't being met.
If the arrest for obstructing wasn't merited, the right way to handle that is to hire a lawyer. Fleeing the scene in a vehicle is never the right approach in America (or frankly anywhere), it endangers the public generally not to mention your own life in particular.
In either case, it shouldn't matter to this case. The man should be put on trial not to decide if ICE's mission is legitimate nor to decide if she was guilty of obstruction or fleeing, but rather for murder. The question of whether he, in that moment, genuinely believed there was a lethal threat to his life is what should decide this case.