Multi-User Editing shares only some assets. (perhaps the packets are lost) (VPN)

During a session with a friend connected via the same VPN over the internet with the Multi-User Editing plugin feature, when I add about 200 assets at once by drag and drop, only about 46 will be shared.
I would like to know what to do to get all the assets to share properly.
(By the way, all assets are shared successfully when on LAN).

The VPN connection is slow and takes about 200ms round trip.
When assets are not shared properly, I get the following warning, which I believe may have something to do with this.

LogUdpMessaging: Warning: Waiting for ack too long. Re-sending 1 segments

Occasionally the following warnings also appear:

LogConcertDebug: Warning: testsession (5965013F4715F52F6481FC92DEE9D96D): Message '32D28E704D5415BD93C98AA068ECF269' (ConcertSession_CustomEvent(/Script/ConcertSyncCore.ConcertWorkspaceSyncActivityEvent)) timed-out sending to 'F7338DDB468D98F2CA0D89B1EE489AFE'.

version: UE 5.3.2
UDP Messaging Setting:

  • Static Endpoints [0] = 192.168.30.10:7000 (server ip and port)

Multi-User Editing Setting:

  • Server Port = 7000

Bump. It has not been resolved yet.