1) Yes you all were right the Bumble Bee goby was a brackish fish
2) Yes the puffer could possibly nip my Betta's fins
3) The puffer in question with its specific species is a freshwater not brackish water dwarf puffer species.
Anyways I exchanged the fish for plants and here s a total run down of the plants in my betta's tank:
Hygrophyla Augustafolia – x 5 stems
Hygrophyla “Polysperma Sunset” – x 4 stems
Rotala “Pearl” x 10 stems
Aponigeton Ulvaceus - x 1 bulb
Crinum Thaianum – Onion Plant x 1 bulb
Nymphaea Lotus Green – Water Lily x 1 bulb
Ophiopogon japonica – Kyoto Grass Plant x 3 stems
Hygophyla difformis – Wisteria x 4 stems
Dracaena sanderiana – White Ribbon Plant x 2 stems not aquatic but thrivin'!