Theme Switcher in plugin

Hi, I need to use a basic theme to get community events manager to work correctly with no errors, which isn’t a problem in the main because the link to it I have included the theme in the link so what the user gets a slimmed down version of the site just for adding events, which is fine just for that part of the process as once an event is created it shows fine within my default theme so all though its a work around the user thinks its nothing of it, what I would like to do to improve on this is to add the theme switch to the community events plugin code so that when ever the plugin was being used regardless of how the user got to my add events page they would view it in my dedicated events theme then once they leave the plugin return to the default theme.

The events code –

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to change the theme just with a URL I just simply use https://mysite.co.uk/?wptheme=theme2

can this be added somewhere within the event plugin or do I need to add something from the theme switcher plugin code ?

Help with this is really appropriated and im guessing that there are loads of folks with a great plugin that conflict with there default theme that may be able to make good use of a theme per plugin hack.

Many thanks in advance

Mark