Drilling without communication is perfectly ok

The Philae lander landed on 67P with some extra bounces, and ended up without it’s solar panels in some shades. Hence it did not have enough power to both drill a core, sample and communicate back all it’s findings.

If we don’t know what we’re doing, we can’t be blamed for failures

Oilfield drilling and well operations are generally performed without much communication at all. The mud pulse system used for updates and downlinks run at very low rates, barely better than smoke signals.

Any drilling engineer in the ESA Rosetta space team would not lift an eyebrow of the failure in communication that was seen on the #Philae lander when the solar panels faded to black.