Sexing newly morphed tiger salamanders

Hi there! I'm new to this hobby and to this forum so if I'm wrong by posting this here please, by all means, correct me!
I have three tiger salamanders, two of which are almost done morphing and one is in the middle of the process, and I'm just curious if it is possible to sex them at this stage and or age? I will be attaching a couple pictures to see if anyone can tell if they are male of female, or if I still need to wait a while. Also if anyone sees something I'm doing wrong please help me out because I'm very concerned that I have not received credible information on how to raise these guys, but I'm trying by best and need as much help as possible because I have fallen absolutely in love with these little slimy things and want to do this properly for their sake.
The pictures are of only two out of the three babies but I will upload another containing a picture of the third baby if necessary
Also if anyone can tell me the exact species or type of tiger salamanders they are that would be awesome!!

I would say it would be unreliable to identify the sex of your little tiger salamanders at this stage from the pictures provided.
When mine are close to water I slope their tank, so as to provide a land area. I add a cave or something for them to hide under. Sometimes you'll find the newly metamorphosed tiger will not readily feed. I provide a few size appropriate worms daily to spark their appetite. If they remain close to water, you may find that they will pop in and out of the water :happy:
I move mine to a soil based tub. I like to have a mixture of soil, coco-fibre and leaf litter, this is 2-3 inches deep. I also have a water dish and various hides . The link below is very useful :- Caudata Culture Articles - Tiger Salamander 101
Also this section has lots of posts with advice and stories of our experiences with our Tigers Species, Genus & Family Discussions - Tiger Salamander & Axolotl (<i>Ambystoma tigrinum</i>, <i>A. mavortium</i> spp, etc.) at Caudata.org Newt and Salamander Portal

I think, from my observation, that I have two females and a male. Two are quite large and round on the belly and the other is small and a lot more thin. The one I believe to be male ans not finished morphing completely but I found him on the land I provided for them. I will be changing their habitat this week to the coco fiber and organic soil mix that I keep reading about. Is it safe to pull them out and put them in a bucket with some water at the bottom to keep them moist while I change their tank? I'd obviously make sure my hands were clean and not use soap and make sure they are wet when I pick them up, if it is indeed safe to move them like that temporarily while I create a better environment that will meet their more permanent needs. I would really like to keep them in their 20 gallon long aquarium and not in a tote box. Any advice is greatly appreciated and needed. I am extremely grateful for the help I have already received!!