I personally have no clue what "Deadline funnel" means?
Could you PM me a link I can see!
As for troubleshooting the apps, I think in case of doubt you can easily turn off any App that might be causing any issues without having to remove the entire code from your funnel... though that's fine too.
Generally, our apps can't distinguish between the purpose of any given funnels all it really care about is whether it's an Order form, OTO page or a TYP. That's it... As long as your page falls in one of those types it should be integrated.
That PayPal error, I guess it means that you might have some wrong parameter, like missing currency, seller email, or in worst cases your PayPal account is misconfigured... I personally need to see the actual page in question in order to provide more insights.