I've already responded to your email on this issue, but I'll repeat the gist of that reply here, in case anyone with a similar inquiry happens across this thread:
The problem with using bundling in your scenario is there's really no way to specify differing order quantities for different items in the bundle. E.g., if you set it up so the buyer orders qty=1 parking pass that bundles some quantity of tickets, that order would only deduct 1 unit from both the pass and ticket products' inventory; however, if you set it up so the buyer orders qty=4 tickets which also bundles 1 parking pass, that would deduct 4 units from both the pass and ticket products' inventory.
What you need might be achievable with a bit of custom javascript in your page, so that when the buyer adds at least qty=4 of tickets to their cart, a link could appear in the cart that allows them to add a parking pass as well. This is similar to what our client MuvEnum used to do, where adding a download item to their cart offered a "Backup CD" add-on option in the cart, and removing the download item also removed the CD; it appears they aren't doing this anymore, but perhaps you could contact them to inquire how they did it:
http://muvenum.com/company/contact-us/
Setting up custom scripting like that is beyond the scope of support we can provide, but we can recommend the competent, E-junkie-experienced developers for hire listed in our directory here:
http://www.e-junkie.com/ej/developer-directory.htm
Another approach occurs to me now, though it may be a bit tedious to set up, using our cart's multiAdd function. This would allow you to post a range of Add to Cart buttons that add multiple items to the cart, each with predefined quantities, like so:
<a href="javascript:EJEJC_multiAdd(Array(
'https://www.e-junkie.com/ecom/gb.php?c=cart&i=YYYYYY&cl=XXXXXX&ejc=2&quantity=4',
'https://www.e-junkie.com/ecom/gb.php?c=cart&i=ZZZZZZ&cl=XXXXXX&ejc=2'
));"><img src="http://www.e-junkie.com/ej/ejadd_to_cart.gif" alt="Add to Cart" border="0"/></a>
Note that this depends on having our overlay-style cart displaying "inside" your own page; just make sure you copy your View Cart code directly from Seller Admin and paste at least one complete block of that into every page with any number of Cart buttons.