Friend Can't Join Server, But Only This Server

So my friend can't join this vanilla server (which is run by my other friend) but she can join other aternos servers, and everyone else can join this server. we have tried everything. when it prompted her to put in the dnysIP we did, then she just got a timed out error message. we tried changing her DNS server address. she re downloaded minecraft THEN re installed it to a new directory. I tried running the server instead of my friend and no luck. she has no firewall, antivirus, or VPN on. She had no mods or texture packs installed. She's playing on the correct version.
The only thing that could potentially be a problem is that she lives in a different country than where the server is being ran from, but then again another friend from the same country has no issues at all playing on the server. i don't even know what to research at this point to help.

heres the error message she gets when trying to connect with the regular IP

and heres the error message when she tries to connect with the dynsIP