The attribute values are 1 lower than the values companions have when you hire them. In classic, Wolgraff started with 4 Strength and Baardvark might have wanted to roll that back. I'm too lazy to read his Scales Readme which might have information.
I'm not sure if a change to Wolgraff's stats can even affect an already started game. His stats should be created when a new game starts. From then on, only manual changes (i.e. when he is in the party) should be able to change them. (and changes by scripts of course, but I think there are none.)
I do not know why companions have one less in each attribute in stats, my best guess is that all NPCs get +1 in each attribute as a compensation for gear players might collect during the course of the game. Companions are normal NPCs until you hire them, so if my speculations are true, they need to have stats in Character.txt 1 lower than the final desired stats to achieve the results we see when we hire them. All enemies need to be adjusted accordingly then too, but it is not more than speculation from my side, no confirmed info.
I cannot say anything about the Vitality thing, I always thought it was a percentage added after base vitality was calculated.
If I look at a player's character sheet on Explorer difficulty - which I did just a moment ago -, it tells me 'From Difficulty Setting: 80%', which is the value in 'new entry "CasualPlayer"' in the unmodified Character.txt which defines the multipliers for players in Explorer difficulty.
I did a quick test, started a new game on Explorer, chose Scarlett as Fighter with no changes, that is then 6 CON, and started. On Cyseal Beach, the char sheet shows 111 vita, 62 from CON and a boost of 80%, which would be 111.6, obviously truncated. Quicksaved and exited, changed Vita of CasualPlayer to 50 and loaded the save, it showed 93 vita, which is exactly 62 + 62/2, as expected. Existed again, changed Vita to 1000 and loaded. Now Vita shows 682, which is NOT 10 times 62.
This can only be explained if the Vitality in the meta entry is added to the one in the individual stat which is 100 for players from _Hero. 62*11 = 682, 62*1 = 62, 62*1.8 = 111.6, truncated to 111.
Where the 62 comes from I do not know, of course it's from some formula.
I checked HP values for different values of CON from level 1 to level 3, they are
1 2 3
CON 5 52 79 105
CON 6 62 93 124
CON 7 72 109 145
CON 8 83 125 167
CON 9 95 143 190
CON 10 107 161 215
Now I can only guess that some (Act Part + 1) multiplier is involved in the formula for the per level increase because Larian loves that ;-). The HP values are rounded or truncated to integer of course. So try it out on different levels, divide it by (level + 1) and then build the average because the values you get should be approximately the same. The value found is what is calculated from CON, and I'm too bad in math to find any formula behind that ... and too busy and lazy right now. I assume it's not too complicated, but for me it is. Testing values with less than 5 CON is work I don't feel like doing, as are values above 10 ;-)
What I would say is that Vitality is a multiplier in % and Vitality of base stat entry and from the meta entry are added before they make the multiplier for the base HP. (So it is not 100% of base and then 1000% of the result but (100% + 1000%) of base.)
Better take back your change to 1000, no matter if you understand why the values are far from what you expected. Baardvark basically doubled HP of all NPCs that have a base of 100 and changed others accordingly, like the Void Dragon from 500% to 600% ;-)
If you want to find out and calculate why you get the values you get, you'd have to beg Raze to dig for information with the headquarters ... and I think they have little nerves for EE modders currently with D:OS2 already postponed ;-)
... or find the base HP formula yourself with the information in mind that all values you see are round()ed, truncate()d or ceil()ed. And that this (level+1) multiplier is probably used in the formula.