This table suggests you should need a FET/BJT to power the coils
The operating voltage of 3.75V for the 5T version you have is well beyond the maximum voltage the GPIOs can supply - if it works it’s just a fluke but not within specs.
The coil resistance would suggest a current draw of ~19mA which would be within specs for the GPIO but may be too little for reliable switching (nominal operating power of 140mW would require 42mA @ 3.3V).
In your schematic we can also not see any flyback diodes.
A dim blue D7 LED is often caused by some brown-out condition which may well be in connection with poor quality supply power (you may able to revive these Photons as shown here)
To sum it up
- don’t feed GND through the board
- add flyback
- use FET/BJT to power the coils
- add filter and buffer caps