Suspect the salvaged batteries have no protection circuit but your flames do. Probably tripped and needs reset. As to how, maybe someone more versed in these things can answer
If you only use them in single-cell lights, you can get pair of Sanyo 2600mAh unprotected for $11 (from KD). If you have proper charger and single-cell lights, you'll be safe even with unprotected cells.
With a good flame 3.5 amps is no problem unless its a fake, you could invest in some redilast ive tested 2600 mAh to 5.2 amps with out tripping, or unprotected NRC18650,s to 6.2 amps but they get warm.