Can Vcontrol be used as an enable on the LT3080?

Yes, it can be used to delay the startup of the IC by delaying when Vcontrol rises relative to Vin. This can also be seen/verified in LTSpice.

Can the Vcontrol pin be higher than Vin on the LT3080?

Yes, it is possible, and in some cases, required to have Vcontrol at a higher voltage than Vin. For example, if you are looking to achieve the lowest dropout, you need to have Vcontrol at a higher level than Vin. For example, with a Vin of 4.1V and Vout of 3.6V, the Vcontrol pin will need to be approx 1.3V above Vout (i.e. Vcontrol = 4.9V) to ensure dropout. The required delta between Vin and Vcontrol will vary depending on the operating temp and load so it is important to check the graphs from page 6 of the datasheet below.