It includes binaries that will run on v6 in the tape - you need to build it for v7. I also don't know if the VT05 is in the termcap file. Plus, a Tek 4014 in the termcap is likely to be not very useful for vi mode as it's a DVST (storage terminal), but I think there may be a Tek 4025 definition in there (as I wrote it back in the day and sent it Mary Ann who was the collector of them).
That said ex is big and it needs a separate I/D (11/45 class) system, so a while ago, I got Webb Miller's s (mini vi) to compile a while back:
https://github.com/udo-munk/s which has much more
modest requirements (it is known to have been ported to 8-bit micros under CP/M) but it assumes ANSI sequences so there is no termcap.