I am not a big user of MIDI files from the internet, but in the past I have used the event editor to cleanup unwanted "stuff"

First I opened the file using <Open Special>, then using the Notation mode, I used the <Event Editor> (#)

All event types are shown, but the filter can be used to select the specific event type you are looking for.

Does this work for you?
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BIAB for Windows Version 2019 (643)
Windows 10 (1909)