WordPress script file version numbers changing in live environment

I have not directly an answer to solve your issue as it (please take a look at the edit part I add),
but this codesnippet (function) could maybe help you to solve the version issues for .js as well for .css files.

/**
 * Remove query (output)string from .js / .css
 * Using filters
 */
function wpse215386_remove_script_version( $src ){
  $parts = explode( '?ver', $src );
  return $parts[0];
}
// for .js files
add_filter( 'script_loader_src', 'wpse215386_remove_script_version', 15, 1 );
// for .css files
add_filter( 'style_loader_src', 'wpse215386_remove_script_version', 15, 1 );

Please leave version numbers away when you use enqueue if there is no specific reason to use them. Add .js filles to the footer to help your pages loading faster, for reference see $in_footer.

Think about updates/upgrades and what can/will happen when versions change and not match with the version(s) you use in your function(s).

The function above has also another effect(a positive one), namely helping to make files easier cacheable. See my answer here for some explanation.

Codex:
register
and
enqueue
the correct way to prevent issues.

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Edit

One of the reasons could be a security or cache pluging (or maybe even
both), so disabling plugins to see which could cause the problem. Enable
debug
in wp-config.php to see if it drops error messages in the
logfile.(if correct configurated the log file will be in the
wp-content folder.