Z-Score to absolute anomaly score value

[mr-price]

Hi,
I am building an app with merlion backend and have trained an isolation forest model on multivariate data. Now i want to provide my users a visual representation of my anomlay score. With a marker separating scores before the threshold and scores after the threshold.
for this I create a PDF plot representation of anomaly scores provided by my Isolation Forest model ( model.get_anomaly_score(data) ) and now i want create marker represent threshold. But my threshold is in Zscore value and to create a marker i would have to convert it into absolute score value. so that i am able to plot.

Since the score are processed using a calibrator i am unable to convert z-score to absolute score value. A guidance on how can i obtain this conversion would be helpful.

I have already tried getting the mean and standard deviation from the score data and then trying to convert z score to an absolute value using : Z = (x-μ)/σ

i want to achieve something like this :