Head gasket but could it be something else?

[Numero9]

Giving the car some TLC and noticed some mayo under the oil cap, given the coolant level was good and it has been doing a lot of short journeys I thought it could be that.

Give it a week and still mayo under the cap but the coolant level is now starting to drop

Are there any other signs I can look for to 100% confirm it is the head gasket or via VCDS?
Also wondering if it could be anything else?

[Octoparrot]

Mayo under the oil cap is normal for this time of year especially if you only do shortish journeys. Head gaskets on these rarely give problems. Top up the coolant and keep an eye on it. If it drops again I'd suspect a leak somewhere rather than a head gasket fault.

[mjmallia]

Short journeys and the cam cover cap extension that reaches up to the engine cover, allows moisture to gather/mix with oil vapor ......... creating a small amount of mayo under the cap at this time of year.

Since this extension has been removed (seal broke with age), I have the cap directly on the cam cover at the moment and there is no mayo issues that I historically got

If it is the head gasket, then the coolant level would be dropping