There are no ultra short throw models I have ever seen which do this. This comes down the the mechanics of the lens design. No UST projectors have a FRONT lens, which is what you would need to do what you want. They use a mirror system and a lens on the back to maximize distance between the lens and the screen without creating additional projector depth. This means the image has to clear the projector, which means it projects upwards slightly. So, it is going to be pretty standard to see 6"+ of offset from any UST projector, plus the height of the projector, plus the mount.

Please understand, you are in a VERY small minority of desired setups. Most people prefer more offset and most people have higher ceilings to work with. So, you are a 1% of a 1% type of setup. Which means you don't have odds in your favor for setup.

There also is a huge gap in availability between short throw and ultra short throw. There simply isn't anything in the .3 or .4 throw distance category. Not that there isn't ANY market for it, but the market isn't that large, and people STILL want a bit of offset typically.

Another factor is the 4K requirement as 4K support is still completely unnecessary in the commercial market by most users. The resolution is too high to make text readable from a normal viewing distance at normal screen sizes, so it is pointless to add that expense to most projectors.

So, you are left with a list like this...
https://www.projectorcentral.com/projectors.cfm?g=1&hide=0&st=1&exp1=1&r=1017&br=3500&br=12000&c=&w=&db=&ar=&zr=&wt=<g=&ll=&wr=&dt=&mfg=&p=&t=&pjl=0&pjw=0&pjh=0&exp4=1&td=&is=&i=d&tr=.2&tr2=.5&exp5=1&oop=2&sort=pop&sz=15#list

Which frankly isn't much of a list.

I think I would shoot for a model like this one and accept that a .48:1 throw distance is as short as you will get while maintaining a lens at the ceiling.

https://www.projectorcentral.com/Epson-Pro_L1490U.htm

In reality, I would reach out to both Epson and Panasonic to see what they have to say on this matter. They may have a short front zoom lens with offset which works for your desired setup. The .35:1 lenses all require the projector to be located in the center of the screen (top to bottom), so that is useless for you. But, models like the ELPU03S lens should work.
https://www.projectorcentral.com/Epson-ELPLU03S-lens.htm?part=10991

Epson can confirm better than I can, and I know Panasonic has an engineering division which can help customers determine a make/model which suits their needs.

As I said, I would reach out to Epson or Panasonic and they should be able to direct you as to a best solution to what may work for you. If those guys don't have a usable solution, I'm really not sure who will.