Resolve - Fusion integration keyer issues

First thing first, I'm completely new to resolve and and fusion. I wanted to check out the fusion integration, so my workflow is probably a mess but this same node network works in fusion 9 with no issues. I've attached some examples of broken frames below, some frames are completely transparent, some only render one small patch in the shadow area, some render half the effects on the wrong frame altogether! This is happening on both shots, and I've checked both files for corruption, they are fine.
I come across this issue with the delta keyer and the ultra keyer. Some frames render fine...

but others come out like this:


I've attached the exported project if anyone cares to take a look and find out what I'm doing wrong
Specs:
Resolve v15.0.0B.043
Win 10 Pro v1803, build 17134.81
Threadripper 1950x (stock clocks, liquid cooled)
128GB RAM
3x titan XPs
1TB M.2 SSD
2x 4TB WD Black (RAID 0)
10Gb pcie Ethernet card
1500 watt PSU
I come across this issue with the delta keyer and the ultra keyer. Some frames render fine...

but others come out like this:


I've attached the exported project if anyone cares to take a look and find out what I'm doing wrong
Specs:
Resolve v15.0.0B.043
Win 10 Pro v1803, build 17134.81
Threadripper 1950x (stock clocks, liquid cooled)
128GB RAM
3x titan XPs
1TB M.2 SSD
2x 4TB WD Black (RAID 0)
10Gb pcie Ethernet card
1500 watt PSU