As a general rule, unless there are major team culture, character, off-the field, or health red flags the NEP FO should be brining everyone in for a conversation and potential workout that has superior talent. If they work out, great. Everyone wins. If they don't get rid of them as soon as possible.
I'm aware of his issues. Aiyuk acted immaturely by taking a selfie while driving 100mph passing the team's stadium. Incredibly stupid. Incredibly selfish (he's married with a kid). He also skipped workouts, etc. Not sure what the 49ers did to him but he clearly had an issue with them over something. He seems like a bit of a rebel/non-conformist (uniform issues) so that is also a concern.
I'm definitely not in the, "We need a numbah one wide receiver" camp and get him at all costs but when players with talent are available, a responsible FO would do their due diligence with prudence and give Vrabes the opportunity to talk to him and see what he can/can't work with.