In the Renown option the DMG tells us that it cannot get lower than zero. I disagree, I think it can reflect an increasing enmity. As I see it, a -5 renown score would lead to a NPC/faction actively trying to hinder the PCs. A +5 renown would be the opposite, helping the PCs as they can.

Here’s how the 7As renown stands after a few more dealings & side quests with Chult’s denizens:

Port Nyanzaru

The Merchant Princes:

Zhanti: +3

• defended the Amnian Fop (showed valor +1)
• played an important part in capturing the pirate ship The Stirge along with its captain (commerce interest: +2)

Ekene-Afa: +2

• freed a spy working for Captain Soshen that had been held prisonner by the Bridgerunners in Malar’s Throat (took side: +2)

Kwayoté: +1

• exterminated the critters in newly acquired mine (commerce interest +1)

Jobal: -3

• have freed a spy working for Captain Soshen that had been held prisonner by the Bridgerunners in Malar’s Throat (took side: -2)
• killed more Bridgerunners that attacked them, with the help of Purple Hands (took side -1)

Jessamine: +2

• secured a shipment of frogmen-made pottery by helping the tribe overcome a crisis (commerce interest +1)
• killed Bridgerunners that were encroaching in affilated Purple Hands‘ territory (took side +1)

Ifan Talro’a: 0

• participated in many events at the Grand Coliseum (showed valor +1)
• crossed swords against Flaming Fist allies (took side -1)

Port Nyanzaru: other factions:

Port-Nyanzaru’s Populace (+3)

• participated in the finals of Liberation Day’s Tournament (showed valor +1)
• captured pirate ship the Stirge (showed valor +1)
• killed the pirates in naumachia event (showed valor +1)

Flaming Fist Mercenaries: -3

• killed Flaming Fists to save a merfolk (took side -3)

Greater Chult

Pink Reef’s Merfolks: +4

• traded with the merfolks (+1)
• saved a captured merfolk by killing its assailants (took side +3)

Three-Cascades’s Frogmen Tribe: +5

• saved the tribe from a terrible plague by getting the cure in the Forbidden Valley (saviors +5)

Valley of Mist’s Albino Dwarves Tribe: +3

• defeated the Caves of Decay troglodytes that were attacking the tribe (defeated a major threat +3)

Plateau of the Aarakocra’s Flock: +1

• made a deal  useful for both sides (+1)

Pick & Axe Company Dwarves: -2

• looted the treasures of Tomoachan (- 1)
• forced a weeklong pursuit in the jungle and finally evaded the Dwarves (-1)