Ok then why upgrade to 64 bit, you can have any windows 10 edition you want once you get win7 in place. Win7 keys are the same for 32 or 64 bit. Here's what I would do. Leave it be and get a Win7 upgrade license, upgrade to 7 then reserve your copy of 10. Do a in place upgrade to 10 which now makes your 7 key a proper 10 key. And since you did so many jacked upgrades, do a fresh clean install of Windows 10 with your 7 key that is now upgraded.
THat would also work but is going to be the same number of installs anyway !!
1- from win vista 32 bit to 64 bit (requires full system wipe to change from 32 to 64 bit)
2- from win vista 64 bit to win 7 64 bit
3 - upgrade to win 10 64 bit
or
1- from win vista 32 bit to win 7 32 bit
2- from win 7 32 bit to win 10 (will upgrade to 32 bit since it is currently 32 bit)
3- from win 10 32 bit to win 10 64 bit (requires full wipe to go from 32 bit to 64 bit)
So really doesn't matter which way he does it the result is 3 installs and the end result is having windows 10 64 bit.

(Only difference is the original method means your final build is an upgrade instead of a clean install but since it is being done off a fresh install of win 7 shouldn't create any problems with remnants from the upgrade process. )
Easier method would be to use an OEM windows 7 license rather than an upgrade from Vista to 7 (OEM 7 systems licenses can be found for about the same cost or cheaper than the Upgrade from Vista to 7

) - that would cut it to 2 installs
1- Fresh install win 7 64 bit
2- Upgrade to win 10 64 bit
