The battery pack is two 18650 cells in series, though.
Again, if there are only two external connections then the battery pack manufacturer didn't intend for it to be externally balanced. Do you know something the battery pack manufacturer doesn't?
Either
1. it balances internally; or
2. it monitors each cell internally and forgoes balancing as largely pointless (the best choice); or
3. the manufacturer decided it wasn't necessary to balance or protect the cells individually and just protects the series pair as a single unit (not a great choice, but for matched cells which they are confident in, certainly possible)
Look for a connection running to the far end of the pack between the cells under the plastic you didn't remove, that will tell you if it's option 3 (no connection) or one of option 1 or 2.
The cells are clearly either very well matched in good health, or being balanced, otherwise the voltage on them would be different.