the syntax in your template is all wrong - see this
https://vborg.vbsupport.ru/showthread.php?t=221560 .
The way you are rendering the template is wrong - see this
https://vborg.vbsupport.ru/showthread.php?t=228078 (or just read the code in the vbulletin files).
What text are you ending up with using your current code? It would really help to know so we know where you are going wrong. When I have problems and need to troubleshoot, I totally simplify it all. Template code - <div> Hello! </div> - does it work? If not, you aren't getting the template called correctly. If it does work, put one variable in it - {vb:var testing} - and in the plugin put $testing = "Hello"; and see if that works. Just keep going at it that way to figure out where your problem is.