What is the name of the poetic device where the author creates neologisms/malaprops to complete the rhyme?

I just learned about slant rhyming where you use a distorted not quite rhyme. Emily Dickinson is noted or these. (I personally don't like these, as they distract. Much like trying to make a pun on Polish the nationality and polish to make shiny just because they are spelled the same way.)

But on the flip side, here are a few that go the other way. Forcing the rhyme to work by changing the word.

Ogden Nash:

Parsley is garsley

Bennett Cerf and the extended abbreviation.

There was a young lady from Del. 
Who was most undoubtedly wel. 
That to dress for a masque 
Wasn't much of a tasque, 
But she cried, 'What on earth will my fel.?'

Or you can just mangle the spelling to enforce the rhyme.

In New Orleans there dwelled a young Creole
Who when asked if her hair was all reole
Replied with a shrug
'Just give it a tug
And decide by the way that I squeole.'

What is this called?

Edit: A commenter asked if another answer fit. I said "The question there is very similar to mine, although the example is hard for me to parse as it's structure is odd. The answer is mostly slant rhyme lacking, the cleverness that the examples above have."

In the extended abbreviations example, Cerf does a fun wordplay. The abbreviations make the limerick scan correctly, but if you don't expand them the meaning doesn't make sense. And the other two expansions don't work as real words, but spoken aloud make perfect sense.

'Masque' is rhymed with 'tasque'. This is visual word play. Spoken it could just as well be mask and task. By using 'tasque', Cerf is adding a visual word play.

In the next one, the author uses exact rhyming spelling, but to make the rhyme subtly shifts the pronunciation. 'Reole' wouldn't be pronounced the same as 'real' but more like 'ree owl' where 'owl' is like 'bowl'. Similarly with 'squeole'.

Where slant rhyming comes across as being lazy and sloppy, this sort of thing is a humourous and clever form of wordplay.

One term that occasionally appears in print in reference to this type of humorously strained rhyming is Nashism, named after the comic poet Ogden Nash, who is mentioned in the posted question and who is famous for using such rhymes to a fault and far beyond. Here is an example of the term (and the style it refers to), from the TOC page of Life magazine (July 12, 1954):

Many rhymesters who try it wind up with a crash
When doggerelizing like Bard Ogden Nash
But this week we give as a model—and as relief from crises engendered by Communism and fascism—
A genuine Nashism
There is a chance heavensent to call all LIFE readers' attention, albeit arbitrarili and strangeli
To a number of other aspects of this week's issue, beginning with the cool elf (no geitcha-girl, really a back-to-naitcha girl) known to her friends as Anna Maria Pierangeli
Of Los Angeli.
Or speaking of elves themselves, but much elfier,
Are the netsuke inspired by a non-Japanese tycoon from Philadelphier [...]
There was sport, writes Bob Wallace, and endlessly screwy,
In his sidesplitting account of the first auto tour of St. Louis.
(If you're one of those confirmed pure-us who calls it St. Lou-us
Sue us.)
As in all weeks there is news that is grim but this week there seems much that is merrier.
Like the goat than can do the ballet up in St. Mary's, Onterrier.
So the mood of our rhyme is not prompted by dreams caused by hashish.
It's just Ogden Nashish.

Another reference (and example) appears in Douglas Parker & Dana Giola, Ogden Nash: The Life and Work of America's Laureate of Light (2005) (combined snippets):

He had initially been hired at Universal Pictures by Carl Laemmle ( whose conspicuous nepotism later became the subject of a widely quoted Nashism: "Carl Laemmle has a very large faemmle").

Other poets who have been associated with this technique are Lewis Carroll, A.A. Milne, and Dr. Seuss. Hence we have this instance from Ellery Queen's 20th Anniversary Annual (1965):

To quote from the newest Ellery Queen paperback anthology (number 9), here are 20 "stories of intensity and some of immensity, and all of (to coin a Lewis-Carrollism, A. A. Milne-ism, and Ogden-Nashism) suspensity."