If I am playing a team with a wildcard and a bunch of figures using the ALT Fantastic Four feat.

1. I know the wildcard cannot copy the ATA, does he copy nothing or the regular F4 TA?

2. If 1 is true and he is using the regular TA and everyone else is ALT F4'ing does he heal when someone with the TA printed on their base is KO'd?

From section 7: Feats of the players' guide under General Clarifications:

Wildcards cannot use team abilities granted through feat
cards. When copying a team ability, unless specified
otherwise, they use the team ability from the Powers and
Abilities card.

So, I would say regular F4 to 1 and yes to 2.

If one of the natural f4 characters is koed, the wild card does not heal as the f4 figure isn't using the ta but rather the alt ta. You cannot use both.

1: would copy normal F4 TA
2: if a F4 was using the alt F4 TA they no longer have the old power and is replaced with the new power. So they no longer have the ability to heal other wildcards though KO.

The team ability for Fantastic Four is whenever someone with the team symbol is KOed, heal a click.

Alternate F4 just changes the team ability and not team symbol. Ergo, I believe you would receive the healing from an alt F4 getting KOed.

Actually it replaces it.

When a character possessing the Fantastic Four team
ability is defeated, each friendly character using the
Fantastic Four team ability can be healed of 1
damage. If all remaining characters using the team
ability are defeated as part of the resolution of the
same action, this team ability cannot be used.

since that whole thing has been replaced with

Prerequisite: Fantastic Four team ability
All friendly characters with the Fantastic Four team ability
have the following team ability instead of the Fantastic Four
team ability: Any member of this team may replace its
defense value with the unmodified defense value of any other
member before any attack roll.

it is not able to be healed since it no longer has the healing TA.

You're right, I was thinking team symbol, when the difference is possess a team ability and use a team ability.

What if he had two wildcards copying and one of them dies?

Only characters possessing the F4 TA (i.e. having the symbol and not using the ATA) activate the healing.

I thought if my WC are WC F4 normal and one dies the other one would heal due to both possessing the F4 TA.

They do not possess any TAs they copy.

Precisely. Only characters with the actual symbol (and Thunderbolts mimicing that TA) possess any given TA. Wildcards and Mercenaries merely get to use the ability in question.