The guild keeps the -58 infamy (though your “contribution” will be reset), so that won’t be bannable.
As for the main topic, game staff have been awful at communicating rules on infamy (and rules in general - here’s the full set), so it’s hard to say for sure.
There are no written rules against anything infamy related, but alt farming and use of exploits to earn infamy has seen people punished in the past.
The punishment is entirely at the discretion of the moderator that finds you. Entire guilds have been disbanded without warning for the actions of one new member, including temp-bans for everyone involved + the guild leader.
That being said, if I had to guess this is probably safe unless your guild really coordinates to abuse it and starts climbing the leaderboard - this is a minor exploit that only really makes a difference at scale.