Don't think that injecting more dye will make the leak easier to find. When you inject dye, the vehicle to carry it into the system is oil. Too much oil is bad for the compressor.

One dose of dye will be more than enough. After exhausting all possibilities of finding dye, removing the radiator is a good measure as previously mentioned. Next would be to lower hush panels under dash and examine as much as you can.

The dye in condensation water is a TRACE. A 4" puddle is enough, but you need the glasses, a powerful black light and DARKNESS. Examine it closely.

Good luck,