[Hummingbird] Hummingbird page caching dos not work on multisite with utf8 pages slug - gives 404

Hummingbird page caching dos not work on multisite with utf8 pages slug - gives 404 error.
In regular site all work on.
With pages in English with English slug all work ok.
Problem only on multisite with utf8 pages slug.

How to reproduce:
1. Activate page caching in Hummingbird for site in multisite: http://kedma.shop.fixdigital.co.il/wp-admin/admin.php?page=wphb-caching
2. Go to page as anonimus user: http://kedma.shop.fixdigital.co.il/%d7%9e%d7%a7%d7%a6%d7%99%d7%a3-%d7%97%d7%9c%d7%91/
3. Refresh the page as anonimus user - you will see error 404
4. In log I see:
2018/09/26 02:20:14 [error] 1801#1801: *424 open() "/home/shop/web/shop.fixdigital.co.il/public_html/wp-content//wphb-cache/cache/kedma.shop.fixdigital.co.il/?????-???/22c42388e15ce00821f8b3e4bb598f67.html" failed (2: No such file or directory), client: 79.181.118.106, server: shop.fixdigital.co.il, request: "GET /%d7%9e%d7%a7%d7%a6%d7%99%d7%a3-%d7%97%d7%9c%d7%91/ HTTP/1.1", upstream: "fastcgi://127.0.0.1:9038", host: "kedma.shop.fixdigital.co.il", referrer: "http://kedma.shop.fixdigital.co.il/%d7%9e%d7%a7%d7%a6%d7%99%d7%a3-%d7%97%d7%9c%d7%91/"

I also can't access the file in browser if using
kedma.shop.fixdigital.co.il/wp-content//wphb-cache/cache/kedma.shop.fixdigital.co.il/?????-???/22c42388e15ce00821f8b3e4bb598f67.html

If I rename "?????-???" to "123" I can access file in browser
kedma.shop.fixdigital.co.il/wp-content//wphb-cache/cache/kedma.shop.fixdigital.co.il/123/22c42388e15ce00821f8b3e4bb598f67.html

Please deactivate page cache on http://kedma.shop.fixdigital.co.il/wp-admin/admin.php?page=wphb-caching after you finish to check.

[Information removed by the moderator]

Software:
Ubuntu 16.4
nginx version: nginx/1.15.1
php fpm7 http://wg3.fixdigital.co.il/info.php