In my case it still keeps claiming i'm using version 1.34, and i only have ETS2 installed.
Upgrading and downgrading versions is nothing new to me, but for the first time the MP launcher keeps on insisting i'm using the old version.
Also updating the MP launcher with F1 does nothing either.
It just "updates", but keeps on giving me the version error.
Theres not much more i can do, changing the ETS2 versions doesen't help, updating the MP launcher does nothing, re-installing the MP does nothing.
And on a side note did reply here once before but seems that it wasn't approved
*edit before posting*
Your MP launcher version is 1.0.0.4 instead of 1.0.0.5 when downloaded from the https://truckersmp.com/download,.
Mayhap this is the reason the version check keeps failing?