I'm kind of assuming that if you rolled up to a tiki restaurant in the United States in your metallic mint green Cadillac, and came in past the decorative waterfall to the smooth sounds of Les Baxter and order your first mai tai, you weren't in for an authentic Polynesian cuisine experience. So what was "tiki food" like?
Don's Beachcomber, opened in Hollywood in 1933, is credited with starting the Tiki Culture. Their food menu was mostly Chinese dishes.
https://www.flickr.com/photos/vic-and-becky/5575359713/in/pool-menus/
The other big player in Tiki Culture was Trader Vic's. They were going for the more high class dining and drinking experience than Don's so their 1940's menu from the Original Trader Vic's location in Oakland California reflects that.
For contrast here is a 1950's Trader Vic's menu from the Portland Oregon location. Note that this version has more Chinese food than the 40s version did.
https://www.worthpoint.com/worthopedia/vtg-1950s-trader-vics-restaurant-1880033534
Since Trader Vic's is still in business we can do a little comparison to the modern menu too:
https://tradervicsatl.com/eat/
As you can see it is still heavily Chinese influenced, but the menu has been updated for the modern palate. It appears that Trader Vic's also modifies their menus slightly for regional tastes, for instance the London version looks closer to what the reopened (and now closed,) Portland location served then the Atlanta version linked above.
The interesting thing about this question is that Tiki was influenced by South Pacific, especially Hawaiian Culture. At that time the Hawaiian population was a mesh of cultures, Native Hawaiian, Chinese, Filipino, Japanese, Puerto Ricans, Koreans and Portuguese. We don't see much of that mixed cultural influence in the early Tiki menus outside of a occasional pineapple or coconut, mostly on the desert side.
Modern Tiki Bars seem to be embracing that mix of culture a lot more though. Hale Pele is a Tiki bar located in Portland Oregon that has made multiple top ten "best tiki bar" and "best bar" lists on both the local and national levels over the past five years. Their menu is very simplistic but still shows some Chinese influence. But also have Hot dogs on the menu (not listed on their site.) One is a Kimchi Dog, the other is a Portuguese sausage.
I've also seen similar menu choices at Tiki bars/Tiki influenced bars in Seattle, and the greater San Francisco area. Some places have completely gone to "modern" Hawaiian dishes such as Teriyaki Chicken and short ribs served with rice and macaroni salad with no overt Chinese dishes at all.