I would not use anything like amber DME or darker LME in any beer, but especially an IPA or IIPA.
There are crystal malts in the amber malt, plus Munich malt, but you don't know how much or what kind, so it's best to stay away from them and use light or extra-light DME and use your own specialty grains.
If your beer is already fermenting, you can't make it an IIPA now. But for the next batch you could increase the grainbill, add some corn sugar (about a pound), increase the bittering hops, and increase the late hops.
1 lbs Munich Malt (9.0 SRM) Grain 1 11.8 %
8.0 oz Caramel Malt - 40L (Briess) (40.0 SRM) Grain 2 5.9 %
6 lbs DME Golden Light (Briess) (4.0 SRM) Dry Extract 3 70.6 %
1 lbs Corn Sugar (Dextrose) (0.0 SRM) Sugar 4 11.8 %
2.00 oz Chinook [13.90 %] - Boil 60.0
1.00 oz Cascade [8.00 %] - Boil 15.0
1.00 oz Centennial [10.40 %] - Boil 10.0 min
1.00 oz Cascade [8.00 %] - Boil 5.0
1.00 oz Centennial [10.40 %] - Boil 0 min
Dryhop with an oune of centennial and an ounce of cascade
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