BS and OSS use the same bathroom. BS always uses multiple towels (drives me nuts). He's under orders to leave at least one for OSS. They have two separate spots to hang their towel(s). Labeled with their names. They don't use each other's towels.

OSS bar is bare. There is one folded clean towel. Checked all over and the only others are on BSs bar.

Do I care? No. Was collecting towels to wash. Gave DH the facts. Evidence points to OSS not showering. This is an ongoing thing so it's a pretty sure bet.

But, no, I'm not 100% sure as OSS could have showered and then drip-dried or toweled off with his dirty clothes or put fresh clothes on a wet body.

The river in Egypt must provide the water for that shower.