Your link:
https://vragen.bvdillenburg.nl/index.php/753697?newtest=G01Q01=01
Tpartners link:
https://vragen.bvdillenburg.nl/index.php/753697?newtest=Y&G01Q01=01
I assume you see the difference?
You can't just say "?newtest=" without giving it the parameter "Y". Right now you are telling Limesurvey that "newtest" should have the value "G01Q01=01" which Limesurvey obviously wont understand. It expects something like "Y". And due to this it also shouldn't understand that you want to pass on that "G01Q01" should be "01".
Help us to help you!
Provide your LS version and where it is installed (own server, uni/employer, SaaS hosting, etc.).
Always provide a LSS file (not LSQ or LSG).
Note: I answer at this forum in my spare time, I'm not a LimeSurvey GmbH employee.