Unfortuantelly, due to high-costs associated with creation of the dataset, it is not going to be released for free at this time.
@inproceedings{sigalov2021losangelesmididataset,
title = {Los Angeles MIDI Dataset: SOTA MIDI Dataset for MIR and Music AI Purposes},
author = {Aleksandr Sigalov},
booktitle = {GitHub},
year = {2021},
url = {https://github.com/asigalov61/Los-Angeles-MIDI-Dataset}
}