Just a few more thoughts....
I am not convinced that "the ball was dropped". There is a lot of time where you are not sure what happened. It is unlikely that nothing was done and no one monitored the patient for hours on end. The ER may have been waiting for the affect of the drugs to wear off for a better assessment. The drugs could have been masking her true underlying condition. Althoug you did mention that MRI was recommended, it may not have ultimately been orderee due to other factors, a recommendation does not automatically equate to an stat order. Perhaps other labs came back that indicated something else, perhaps after further reading of the CT scan they realized the bleeds were old bleeds and since she wasn't recovering, that she needed in-patient monitoring.
Before futher judgement on inappropriate care I would love to have known what other labs, medications, consults, GSC scales were.
I think it is hard to know what was her previous baseline status without the influence of drugs.
While there are lots of reasons why she presented on your unit they way she did, there is lots of gaps in information to truly determine if she received inadequate care.
If your team feels this was a potential deviation in care, is your team allowed to do a Root Cause Analysis? This way everyone could see the timeline and providers involved could explain the assessments and reasons why MRI was ultimately not ordered, again, the MRI was only a recommendation not a STAT .